Where possible the screenshots provided have the gun cross hairs pointed at the collectible. I've also backed up a bit to give a better view of the surroundings to help with orientation. Some collectibles may be combined into one description if they are located very close to each other.

I've tried to lay out the guide in the way you'll most likely encounter these items to avoid backtracking as sometimes areas become inaccessible. You may want to have this guide open on a secondary screen or device as you play. For your convenience I've also included all weapon upgrades and maps though they aren't needed for any achievements.

Readable 1: Immediately across from the cell you start in is an office you can jump through the window to access. Its on the table on the left.

Readable 2: Move to the open cell to the right of the breakable wall grate mission objective. The card is next to the corpse on a table.

Gold 1: Inside the room with the switch you access via the breakable wall there are a couple shelving units with an open cardboard box. The gold is inside.

Upgrade 1: On the second floor of the large surgical area with the two officers, the room with one of the officers has an upgrade on the corner of the green console.

Gold 2: After exiting the surgical area before breaking the grate mission objective look to the crates on the right for a hidden gold bar.

Readable 3: Directly to the left of the breakable grate, its on the bookshelf.

Readable 4: After passing the autopsy tables the card rests on a console in a darkened alcove.

Map: Make your way to the opposite side of the second floor of the surgery, the map is sitting on some chairs in an alcove.

Upgrade 2 and Gold 3: Refer to the circled areas of the screenshot. Past the second breakable wall after passing the third floor of the surgery you should see a bunch of crates in front of you. Shoulder charge them and you'll find a secret room with the upgrade on the floor. The gold is on a crate next to the upgrade.

Upgrade 3 and Readable 5: Refer to the circled areas of the screenshot. Continuing on after the last set of collectibles you will enter a large multi-story room. Look left and you should see a locker room and right next to it a small office. The upgrade is on one table and the readable is on the opposite.

Readable 6: Upon entering the building in the first apartment look to the right on the cabinet.

Readable 7: Third floor after entering the fenced-in rooms look to the desk on your left.

Readable 8: First bedroom on the right, on top of the dresser to the left of the bed.

Gold 4: After busting through the wall in the bathroom the gold bars are located on the end table to the right of the bed.

Gold 1: Above the shallow grave where you start and ahead of you are some shelves. You need to go up the stairs and to the left to find a breakable wall that you can use to get access to the area above.

Readable 1: After defeating the officer and his troops, look for a room with a radio setup on a desk, its on the far end.

Readable 2: Once you've entered the large room with the forklift stay to the right side and look for a desk behind a stack of pipes.

Map: In the same room continue up the slope and look for another forklift to the right, the map is on a table next to it.

Readable 3: Once you've cleared out the enemies in the loading bay, look to the left of the sliding doors for a desk.

Upgrade 1: To the left of the booth with the switch you must hit to continue is a small room with a card table.

Gold 2: Once you've exited the sewers, follow the short chain link fence to your right to find the gold partially obscured by a broken wooden box.

Readable 4: Inside the room with the red and black floor look to the counter with the cash register.

Readable 5: Run down the street to the diner where the officer is camped out and look behind the cash register at the end of the counter.

Upgrade 2: In the kitchen of the diner on the prep station is the second upgrade.

Gold 3: After dispatching the robot dog use the smaller boxes to get on top of the shipping crate in the middle of the area and leap to the balcony on the left. The gold is on a table at the end.

Readable 6: Head through the auto shop and look behind the cash register on the counter.

Readable 7: Enter the police station and jump behind the front desk, it will be on a recessed section on the left.

Gold 4: On the second floor of the police station in the interrogation room. You must bust the door down with sprint to get access.

Readable 8: After hitting the switch to go down into the jail cell area look to the desk right in front of the mission objective.

Map 1: After cleaning out the command center area look to the right side of the room for a hallway on the first floor. Around the bend is the map.

Readable 1: Immediately after picking up the map turn around so you're facing the large room and look ahead to the desk slightly to the left of your view. The readable is next to a can and some pie (pie not shown).

Gold 1: After entering the room from the second floor of the command center look to the right, the gold is sitting on a seat.

Readable 2: Exiting to the left of the room with the gold bars you'll see this readable on the desk in front of you.

Readable 3: After passing the open barriers to the right of the previous readable, directly ahead on the counter is the next one. You can either grab it from here or walk around to the left to get inside the room itself.

Readable 4: Inside the room with the presentation the green cabinet on the right has an In/Out box on the corner, its on top.

Gold 2: Down behind the row of chairs and the overhead projector is a box with armor and the gold bars.

Upgrade 1: After hitting the button on the desk to open the secret door, walk down the stairs and you should see the upgrade ahead of you on a small table.

Readable 5: After taking care of the two guards in the room behind the upgrade look to the console on the left before exiting.

Readable 6: Once you've cleaned out the large room with the two officers head up to the second floor and look for a room with consoles overlooking the main floor. The readable is on the left side.

Map 2: After exiting the container turn around and walk behind it and you should see the map leaning against some barrels.

Gold 3: From the container you exited turn left and walk to the end of the room. Behind the vehicle is another container and behind that, a crate with a model airplane and the gold.

Readable 7: After dispatching the two officers and crew, walk back up to the second story where one officer was located and the readable is located on a desk in the corner.

Upgrade 2: In the long hallway labelled "V.R.I.L. Projekt" at the end are a bunch of crates, the upgrade is on top of one of them.

Readable 8: Once you've made it back inside you should see a long room with a baggage car and trolleys in the center of the room. The last readable is on the car's seat.

Gold 4: To the right of the baggage car is a room marked "Erdumbildungslabor." Look in the glass cubby holes on the left side next to some containers and you should see the final gold bars.

Readable 1: Right in front of you on the shelf where you start.

Readable 2 and Map: Refer to the screenshot. After exiting the duct, on the desk to the front and left of you. Right next to the map is the readable near the typewriter.

Gold 1: Across the room from the desk mentioned previously is a gold bottle on a low table.

Readable 3: In a large room labelled "Uberwachung" (has a projector with your face displayed) on the right side on top of a cabinet.

Readable 4: Also in the same room but on the far left side on a desk.

Gold 2: Right behind Readable 4 in an open desk drawer.

Upgrade and Readable 5: Refer to the screenshot. In a smaller room named "Uberwachung" (has an officer in it) on the table. The upgrade is near the middle while the readable is on one of the ends.

Gold 3: In a room called "Beweismaterial" on a shelf in the far right corner.

Readable 6: In the interrogation room "Verhorraum" on top of the table.

Readable 7: First floor of the multi-story room leading to Hans, on top of a desk on the right side.

Gold 4: Outside of Hans' office to the right, on a low table.

Readable 8: Directly on Hans' desk.

Gold 1: On the tailgate of some kind of vehicle parked in front of Stage 23.

Map: Inside Stage 25 immediately to your right.

Readable 1: On the crafts table directly behind the map.

Readable 2: Stage 26, on a small cart with a megaphone in front of the crashed plane prop.

Gold 2: Stage 26, on a work bench next to a model building.

Readable 3: Inside the red room overlooking Stage 26, on a table next to a film camera.

Readable 4: In the large room with the officer, on the desk at the far end.

Readable 5: Take the left hallway from the readable mentioned above and look to the table with the flowers on it.

Readable 6: After entering the film library, on a table next to a bookcase on the right side.

Gold 3: Far right of the film library, on a table.

Upgrade: Again in the film library, on a table with a marble bust directly across from the entrance mentioned for Readable 6.

Readable 7: Make your way up to the second floor of the round auditorium and the readable will be right in front of you on a table.

Gold 4 and Readable 8: Right next to each other on Lorenz' desk.

Gold 1: After entering the large area at the beginning, right in front of you on some crates.

Map: Directly to the right of the gold bottle above, on a metal trolley.

Readable 1: To the far left of Gold 1, on a crate next to a large window.

Readable 2: In the first large command room, on the floor.

Readable 3: Right next to Readable 2, on the console.

Gold 2: Still in the same room, on a corner of the large table in the center.

Upgrade: Once again, same room this time on the far corner console.

Readable 4: In the hallway between the large command rooms, on a crate.

Readable 5: In the north hallway of the command room with the button to continue the mission, on a crate.

Readable 6: In the second command room with the button, on the large table in the center.

Gold 3: After exiting the second command room, walk toward the wall in front of you and duck, you should see the gold bottle in a crawl space.

Readable 7: Follow the mission objective until you reach the generator room where Dunkel taunts you, the book will be on a small crate next to a pistol.

Gold 4: Once you've entered the generator room turn to the left and you will see the final gold bottle in a bucket next to some lockers.

Readable 8: Walk down towards the far side of the generator, down the short stairs and turn around, the last readable is on a crate.

Readable 1: Approach the containers in front of you and double jump to get on top, then look to the left and below you to see an open container. Card is on a table inside.

Upgrade 1: Jump back up on top of the containers and then up into the control room above you, upgrade is located on the console.

Gold 1: Make your way to the opposite side of the room below the mission marker to find a forklift and flat bed loaded with concrete slabs.

Map and Readable 2: Refer to the screenshot. After walking through the ducting and taking care of the enemies in the next area, look to the right under a catwalk for a tool bench lit by an orange light.

Upgrade 2 and Readable 3: Refer to the screenshot. Once you've walked into the storage area look to the sealed area to the left. After the door has opened and you've taken care of the Nazi inside you'll see these items sitting right next to each other on the counter.

Readable 4: In the room with the sealed vent (mission objective) right next to it on a desk.

Gold 2: After dropping down into the next area walk up the short staircase where the Nazi was talking to the general and look on one of the shelves.

Readable 5: On a small table next to a pillar in the center of the room.

Readable 6: After interacting with the red table, make your way up to the catwalk to a cluster of consoles, the note is next to some food.

Readable 7: In the break room while following the mission marker on a table.

Gold 3: After ascending the elevator make your way into the room with the forklift and get onto the catwalk. The gold is located behind a barrel next to a green door.

Readable 8: After continuing on through some ruined rooms look to the right to a side room with a bunch of file cabinets.

Gold 4: In the room with the trucks and the mission exit there is a half-track in the corner. The gold is sitting on one of the tread guards.

Readable 1: On top of the console you have to use the mechanical legs to reach at the beginning of the level.

Upgrade 1: Right after exiting the duct into the storage room you should see it right in front of you on the top shelf.

Gold 1: In the large area with the two officers towards the back of the room are four containers with slightly open doors. Check the one on the right closest to the direction you entered originally.

Readable 2: Enter the command center overlooking the room you were just in and look for the card on the row of consoles next to the windows.

Map: In the same room mentioned above propped up against a wall.

Readable 3: After crawling through the red ducting into the red command room look to a swivel chair on the left side on the first floor.

Gold 2: On the second floor of the same room, jump up on the cable runner and look in the corner.

Readable 4: After clearing out the train station room keep to the left side and head to the room with the mission marker for the switch. Check the left side of the room for the readable on a console.

Upgrade 2: After flipping the switch, head through the now open door and you will see the upgrade on a crate directly in front of you.

Gold 3: Once you've exited the duct and entered the room with the pistons look directly ahead and slightly left. You will see that there is a guard rail missing and you can drop down into the secret room below to collect the gold bars on a barrel. Note that you can see the barrels and the gold by looking down through the grate immediately after exiting the duct.

Readable 5: In the room with the firing controls for the second gun look to the right side of the console bank next to a desk fan.

Gold 4: After the ambush continue on until you enter a locker room. There is an open vent in the ceiling directly in front of you, double jump up into it and turn around for a well-hidden gold bar.

Readable 6: Back to the locker room, check the middle section of lockers for a readable on a bench.

Readable 7: In the middle of the room with "Sektor 2" written on the walls, on a table.

Readable 8: After opening the first set of dividing doors for the missile, look on the right hand side of the room and you should see the card on the floor in front of a radar device.

Map: Directly in front of you after starting the mission.

Upgrade 1: Walk forward from the previous collectible past the two talking guards on your left and you'll find an access panel behind a stack of crates. The upgrade is inside.

Readable 1: In the starting area in the far corner near one of the officers on top of a radar console.

Readable 2: Make your way to the top of the sub docks (jumping over the suspended sub) towards the locked duct cover, the readable is next to it on the left.

Gold 1: Make you way through the multi-level red lit area and head to the very end (bypassing the obvious exit door to the right on the ground level) then engage your mechanical legs and look to the left. You'll see the gold bars on a partially hidden catwalk.

Readable 3: Head back through the door we skipped earlier and make your way up with the mechanical legs. Before dropping down into the room with the two officers turn around and make your way to the right to find a hidden nook with a note on a crate.

Gold 2: From where you dropped down, look to the left and you'll see a duct opening above a white pipe partially illuminated by a light. Crawl in there and you'll find a hidden room with the gold bars in a supply crate in the back.

Readable 4: Make your way through the area until you've found the duct hatch, look to the radar console on the left.

Upgrade 2 and Readable 5: Once you've made it through the vertical areas with multiple locked duct hatches you'll be in a small series of rooms with two officers. As you make your way look for a small room on the left that has both the last upgrade and a readable item.

Readable 6: Before opening the duct hatch to continue, turn around and in the small storage alcove for the next item.

Gold 3: Immediately after exiting the short duct from the last locked hatch, turn around and use the mechanical legs to get up to the ledge above. You should see the gold bars as soon as you jump up there.

Readable 7: In the banquet room, on a table on the right side.

Readable 8: The last readable is on a trash can in a room to the right of the elevator.

Gold 4: Once you've killed Schwartz, look for the last gold bar on top of a green console to your left.

10/2/2018 - Version 0.6 - Initial upload with both Gunslinger Joe and Silent Death's sections complete.
10/3/2018 - Version 0.9 - Completed Captain Wilkins section. I think the guide is done.
08/1/2019 - Version 1.0 - Added missing upgrade from Captain Wilkins Vol. 3.

Thanks:
HeroKing and Cdr Knob Cat for pointing out I missed an upgrade in Captain Wilkins Volume 3!

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