Great build, lots of nice features. I'd seen your shower setup in a different topic but not the build thread until now. Great work all around. What else have you done with the other storage compartments? needs a skylight.
The steps will work well enough with a larger backer plate on the inside. A ladder can be modified with some length straps attached to teh ladder uprights and lapped over the edge and across the roof, anchored to the roof skin, to take the ladder load.
Oh the shower is best luxury item on the rig. Skylight? One of those camper roof vents would have been perfect. I put a lot of thought into it, but as we used the truck camping here and there, found out that we really didn't need it. The insulation keeps the heat from the sun out of the truck, and the led lights inside do a great job reflecting off the foil insulation and is maybe too bright in there. Besides, I looked on the roof, and have no room to cut something in. Oh well.
The folding ladder steps to the roof work great. They are bolted in the corner of the box and you can jump and pull on them and don't deflect at all, the whole truck moves!
What's in the other compartments? Well lets have a look...

Electrical cabinet. Contains the generator control panel, solar controller, air compressor controls, aux fuse panel, inverter, fire extinguisher, two way radios charge dock, streamlight litebox charge dock, microwave, and of course the diesel fuel tank filler.

This is kind of like the adventure cabinet. Climbing gear, rope, helmets, tent, caving gear, binoculars, head lamps, toilet paper, and other misc stuff.

Kitchen pantry. Anything and everything food, cooking, and cleaning. It's a little low on food stock right now. But there is cans of food, soap, sponges, can opener, matches, lighter, utensils, collapsable colander, cast iron dutch oven, a cast iron skillet, and a bunch of other stuff. Tried to fit fit the cast iron griddle/grill in there, but it fit better in front of the fridge.

I guess we can call this one the kitchen counter cabinet. One of the two compartments that the door folds down and can be used as counter space. In here there is the dual burner camp stove, steel handle/hook for the dutch oven, and a folding camp table.

Some general storage for whatever can fit. Pintle hook hitch attachment, chain and things, MRE's, garbage bags, and even some card games.

This is primarily a tool cabinet. special automotive tools, torque wrench, grinder, hammers, hacksaw, sockets, wrenches, torx, allen, multimeter, auto stethoscope, pipe wrench, repair books, safety glasses, and much more. Also up top is the air hose reeler, magazine rack, and first aid kit.

Sort of another tool cabinet. Air tools, strap wrenches, pry bars, screwdrivers, pliers, fuses, wire brushes, tap and dies, drill, drill bits, files, punches, chisels, markers, pencils, zipties, cable clamps, sandpaper, oxyacetylene torch, extra starter relay, tarp, awning walls, shower curtain, and a bunch of other ridiculous stuff.

More tools and fluids cabinets. Fluids for everything on the rig, engine oil, gear oil, transmission fluid, etc. Chainsaw, 2 cycle fuel, spare filters, spare engine belts, WD40, locktite, brake cleaner, bug spray, adhesives, white gas, axle hub socket set, bearing pullers, bearing grease, funnels, hydraulic jack, and various vehicle system testers.

The other fold down counter cabinet. More oriented towards vehicle emergencies. Jumper cables, tow strap, shackles, wheel chocks, extension cords, ammo can, and when all else fails and your stranded, a frisbee.

Water pump cabinet. Pump, various hoses, attachments, duct tape, water purification system, road flares, and rocket flares.
There is a lot of stuff in there, I can't list everything, but that's how the cabinets are setup for the time being. Other big items like the gas lantern, chairs, scuba gear, and inflatable zodiak boat goes underneath the sleeping bunk and behind the fridge. Aside from filling up the pantry with food, packing clothes, and whatever else we need for a journey to nowhere and everywhere, the rig's ready to go! Maybe we'll start the trip in the next few weeks. Need to do a small weekend trip, beat the truck up, use all the systems, setup and take down everything, and make sure everything works and in good order. As you can see by the cabinet pictures, the truck has enough tools to pretty much repair anything right from the truck, anywhere. Only other thing I really want to pick up and carry is a spare starter since it is not manual and therefor cannot really push start the engine...