Thanks Jim!
The ones I am looking at are 60" by 43" (
https://www.rvpartsnation.com/rv-fur...-sofa-sleeper/), so the backs would be taller and probably not work. I figured I may need to mix and match some of the frame pieces so they would fold up against the wall for loading the bikes.
I may just have to go with custom made cushions, though I've never been really happy with the positioning of the backs when in couch mode, made the seat much too narrow to be comfortable, even for a small person like me!
The 2100 definitely had some design flaws that may have looked good on paper but lacked in functionality (like the shelf in the middle of the shower wall instead of in the corners!).
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