Here's one I put together for on call repairs in the open pit mine I work at. The frame of the bed came from a wreck and I used it as a starting point, and skinned it with diamond plate.
Purchasing is an impossible task, so most of this was done with whatever was on hand, or if i could order something, I ordered 5
I had a big focus on job site safety, the guys that run these trucks run them round the clock on uneven surfaces, falls and rolled ankles are common. I built this to do everything from the ground, the compressor is controlled from a box behind the cab on drivers side, there's a dump valve so compressor can be dumped and started, there's air pressure gauge and volt meter for the 24 volt system right there at the drivers door, air hose reel right there, drops close to the truck to prevent tripping. Big tool boxes on drivers side so he can do 90% of his work without walking around the truck, I built the post on the back as a hand hold when you need to get in, a place for a work light, and a place to wrap jumper cables.
I cut in removable panels to access the top of fuel tank and def tank, welded nuts underneath, built in trash can and rag bin, set compressor back from headache rack a foot for repair access, and used that space for the ladder storage. All hoses and fittings are tucked away, shrouded or whatever to prevent damage.
the flammable cabinets get smashed often, so it's easily replaceable with a fabricated strap and threaded holes
the boxes are wired for lights, but the led strips that purchasing came up with sucked and never got done right
I didn't like that I had to put the extinguisher on passenger side, i think I forget if i put one in the bottom box on drivers side
Painted the thing black, then hit the deck with raptor liner. In the end, it would have been better to skip the paint and the labor hours on it, and just buy more raptor liner
