Installed the heater assembly today. The black material is a high temp fiberglass type material I had left over from a previous project.....this will prevent heat transfer from the element to the chassis.
I hear you....off grid can be fun. We do a lot of trips with our XP900 SXS, you gotta haul it......so it's toy haulers, generators and all the other stuff that goes with it.
BTW, you can't even hear a Honda 2000 if it's ~15ft away
I used 5052 because it bends easy and I had some on-hand....I also have some 6061 but it is tough to bend without cracking. I would have liked to use SS but it meant a trip the the steel yard.
I am not too worried about corrosion....I can always replace the shelf supports if necessary.