[freebeard]

The bumpers are one or the other. I used to be able to tell by counting the ribs.

I replaced 50% of the flooring and scabbed patches on 40% of the crossmembers, but the aluminum I got to re-side it wasn't tempered well enough and the wall collapsed. It never picked up steam again after that.

Very simple construction: A 5" steel spine with 6" steel channel crossmembers, each with a bolt into the deck on the end. Then an aluminum U-channel on it's back to make a bottom plate for the double wall. If I ever make a teardrop it will be much like that.