I've had an idea for something like a sleeper unit for quite awhile now. To many projects on the go already so it's not likely to ever happen by me. But.... your welcome to use the concept. I've seen a couple of examples of water hauler or oil tanker rat's and considered making the tank the camper/sleeper. If there was a side skirted area out and down from the frame, one side could be made into the kitchen/cooking area and the opposite side used for storage. The cab end of the tank could be open into the back of the cab but partitioned off with naugahyde or canvas. While the 'back' end of the tank could swing up and be open but be locked shut from the inside. I was thinking that the side of the tank would have a name or logo, do this on a opening panel that also lifts up on compressed struts but has a slider window behind it. One on each side for a bit of flow through air on the warm evenings. Depending on how wide it was, it would be the deciding factor of it being a one or two person rig. The ideas are endless, and I would love to take a run at this but like I said...to many irons in the fire already.