So my old boss gave me a brand new generator for free that I couldn't pass up. I know it won't fit as is, and that it can't run in that tiny space for cooling purposes, however. Where there's a will there's a way! Pic up a cheap generator from a Costco for under 500 bucks. Cut it down to the bare minimum for less weight and smaller size (remove upper framing). Slightly expand the compartment if possible (mine has extra room under the booth seat in the Sun Land Express). Ditch the gas tank and get a line going from the gas tank like you would for an Onan.
Sure you can't run it while driving, but it's stored, not hanging off the back, and ready to pull out and run. Sure it's ghetto, but cheap! Seriously, why spend 3 grand on something you'll barely use.