I honestly cant decide if this is genius or ridiculous. I see where they were going with it, and I like the idea, but picturing the shell on my truck, I don't see having anywhere enough headroom to make it work.
I think the shells were taller back then. Gas was cheaper, gas mileage wasn't so important, and they weren't so concerned with aerodynamics as today. If you don't care about that, it is still possible to get commercial shells as much as 40" tall.
Exact same layout as in our new (to us) T@B camper. U shaped dinette that takes a table to turn into a bed for sleeping. Looks like a relatively easy build also.