Just did this a few months ago - 26' Uhaul. I didn't have the glass installed. I definitely wouldn't put it on the gear. I kept it on the table I built and the table just fit (talking 1" on either side) between the raised wheel wells on the floor - something I wasn't planning on having to deal with. I mounted the engine mount to secure in front and tied off the tail as you can see in the pic. 700 miles and not a mark on anything. Pretty big undertaking - glad it's over
I included this shot so you can see the table it was on:
