My carpentry skills are almost non-existent, so I wanted to keep the steel frame as a foundation. Getting the couch down to just the parts we wanted to keep was ... interesting. I managed to get the back off in one piece, apart from the hinges, and then we cut off the fabric and cords holding the foam on. At that point, we had this:
Those hinges were a real problem, though. We just couldn't figure out how to get them off. Finally, I went to Home Depot and bought a steel-cutting blade for my reciprocating saw. Muahahahah! I dulled two blades, but managed to get the hinges out of the way.
So, then we measured the space and cut a few pieces of MDF board to fit with one edge on that wooden rail on the wall and the other on the metal frame. It needed some spacers to come out level, but in the end we had a nice platform. And yes, those are zip ties holding the spacers to the frame.
It's almost big enough for a twin size mattress, but not quite, so I ordered a custom foam mattress. Incidentally, these guys http://www.foamforyou.com/ are great. Their web game is weak, but they're super helpful on the phone. I've also had them cut me new cushions for the dinette.
I added a non-skid rug pad on top of the boards to keep the mattress from wandering out into the walkway. Once the mattress is on and you throw a quilt over it, it looks nice, and the carpeted door that flips up from the floor still works perfectly - or, at least as well as it ever did.
