Andre & Jim,
I didn't have the capability to build the camper box, so I hired a local Truck builder to make the box. It is standard Semi-Trailer construction using steel "hat sections" for the inner framework with the aluminum skin riveted to it. The rounded front corners used standard castings the you would find on most semi-trailers.
It was basically hand fit to the 712's bed, fenders (seat) and over the frame rail. Extended the width a total of six inches and the length ten inches. The width was primarily to give a little more room inside and the length extension was to include the interior step within the camper door (did pickup some space on either side of the walkway).
My two primary requirements were that I could walk around on the top (roof strength) and it should not leak! So far those needs were met. Base weight is about 800 lbs. I weighed my truck without the box and it is 5090 lbs with about 10 gallons of fuel.
After I finish and reinstall it I'll go and weigh it again.
My greatest problem has been the amount of hand fitting for the interior items. That Takes A Lot Of Time!!
Not a Motor Home, but a minimal camper with some conveniences.
2 burner cooktop, refrigerator, sink with fresh water and holding tanks. All interior lighting is LED to reduce the electrical requirements. FRS/GRS, CB, VHF transceivers, Laptop operated GPS (larger map size)and plans for 15" tv. A portable potti is on a slide out drawer (a convenience for my better half).
Anyway... Got to get Back to Work

Thomas E.
Sonora, CA
712 Camper
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