Yes the exhaust is a problem. I bought a set for a road trip last summer and burned thru the bottom and the fanny pack inside. I rearranged them and put foil in the bottom which helped. Then I cut out the entire bottom and riveted a copper sheet on the outside and aluminum inside with fiber glass between for the return trip. That mostly worked but the material near the middle strap seems to have softened and isn't happy.
I made some angle brackets and will mount a plywood shelf on each side and strap the bags to that. I'll put metal and insulation on the right side and expect this to work fine.
The bags are sufficient for a week trip with light camping gear, much longer if not camping. But the exhaust and having a monoshock which allows the bags to swing into the tire makes mounting a challenge
I have a brand new, never used, Nelson-Rigg (CL-1070) 22.9 liters expanded bag for sale. It fit my Scrambler just fine. But purchased for a long trip but had to cancel. It is yours for $60.00 + shipping.