The reasoning for not building over the A Frame is to allow van to turn corners with hitting tug. A fifth wheeler or gooseneck pivot doesn't have this problem. Build a dog trailer & you could have a two storey RV view.
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Possum; AKA:- Ali El-Aziz Mohamed Gundawiathan
Sent from my imperial66 typewriter using carrier pigeon, message sticks and smoke signals.
If this is high enough to not cause an issue with hitting the vehicle when turning its going to be very high, which is a real issue with getting in and out of the bed particularly as we age. There are also of course issues with ball weight. There are vans/campers with drop down beds over this area like Expanda's, but I really can't see how it works with a full size van.