You have a Tacoma that gets mid-twenties with a camper shell on. Why not put the time, energy, and money into one of those aero-toppers (assuming you haven't)? You'd improve the economy of a vehicle you already own, and you could design it to go level with the cab and include tent-sides like the
Aerolid
Then you could make yourself a nice truck bed setup.
I mean if you want to hack up and stretch a hybrid for the heck of it, then knock yourself out. It just doesn't seem like a
practical solution.