This is similar to a camper I just purchased used...
That works similar to the Bethany "Pickupper" camper I found on Craigs list...
Top goes up and sides fold out... only thing different is that the sides on mine fold out to be double beds on each side and the "galley" is across the front. I see there is another one listed on MN Craigs list again.
I attached the brochures from the '70s for more info. on "my latest project" posting.
I'm in the middle of updating the galley systems right now... new power, water and 12v refer. also planning space for a microwave/grill and new porti-potty. Also adding a outside shower system.
It is suprisingly spacious when the top and sides are extended. Seems roomier than a typical pickup camper. Mostly due to the beds on either side leaving a 4 X 6 foot open floor.
I bought it for the low weight and low wind resistance you mention.
I also saw a set of similar plans on ebay...
"Young enough to know it all, Old enough to know better"