Alright y'all this starts the build out of a budget camper built on my 2012 F-150 XL 4x4, RC/LB. After weighing all the pro's and con's of a truck tent or a used cap, I decided to buy a cap. I found this Leer aluminum shell on Craigslist for $100, in near perfect condition. It just needs a thorough cleaning inside and out, and I've got some fit and finish issues I need to sort through with how it sits on my truck. But that's mostly because I'm anal and I like things to be perfect when it comes to my truck.

Plans for the build-out include some insulation inside the shell to reduce noise and heat. I also want to fabricate some sort of rack system for the top of it to hold extra gear. I just picked this up today so this is pretty much how it looks
My version of this project...
My dad and I built a "Redneck motorhome" back in the 70's for when we went hunting.
Dad had a '74 Chevy 1/2 ton and got a Smittybilt canopy for a 9' Ford from someone for a song.
We took some plywood and 2x4's and built a 2' tall section that sat on the bed, then we'd put that canopy on top of that.
Somewhere, he picked up a big roll of vinyl backed high density foam. We cut that out so it fit the floor of the bed and that was the "carpet".
Dad took some aluminum angle and laid it across the bed rails, laid a piece of plywood shaved down to 3' wide, inside of it and put some foam on the plywood.
That was his bed.
I slept on the floor of the bed, under him.
We used military mummy bags (real goose down ones!

) and stayed toasty warm, even when the temp got down to 0.
Cut the rest of the plywood to about 1' wide and nailed some 2x4 legs on each end and ran another 2x4 across the front, to reinforce it and that sat over the wheel well.
We made 2, one on each side.
They served as benches to sit on and tables to place the Coleman stove and other various sundry items on.
We had a problem with the inside sweating real bad.
The canopy had a square tube metal frame that the aluminum shell was laid over. We cut 1/2" thick Styrofoam pieces to fit inside the grid of the frame and glued them to the roof with some kind of special calk he found that advertised excellent adhesive properties.
Cured that sweating problem, although once in a while, one of those squares would fall out and we'd have to glue it back in once we got home.
Made the inside much quieter and really insulated that canopy nicely.
We ended up doing the sides, too.
It really was a nifty little rig and dad had a penchant for BOLTING things together, so that it could be torn down, and/or modified, easily.
We could put it up and load the truck in about 2 hours.
Same with unload and tear down.
That's how we did it, 45+ years ago.
I hope you can glean something from that.
Feel free to ask about anything you don't understand.