My dream rig would start out just like this so take this for what it's worth based on what I have read. They get heavy and overweight a lot faster than you would think so the dual to single really needs to be thought out. I like duals so that would be easy for me. Just keep the weight of every little bit in mind. I would put more of a hatch as aposed to a door to the cab because on my e350 4x4 camper van I don't find myself hoping from the driving position to the rear that often. If I do I usually walk around to climb in the side. Same for both directions. I'd do a small crawl thru and keep the driving area for driving and camping in the rear. For a shell I'd consider a used pull behind camper and engineer mounts to the truck frame to compensate for more flex than you would even think possible. Wish I could really help so good luck!
New River, Arizona
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