Interesting. Always wondered what was under the carpet in these. I've seen photos of guys' gutted shells, but never a camper unit disassembly process like yours. Never got that far with my former Chalet #1747. It had better-than-average original carpet, but that back step-down area seemed too 'bendy' for my preferences. Dead, rotted plywood, no doubt. Chinook used really lousy quality wood. Be sure to show what you find inside your rear door. I had an RV shop fix mine (outer fiberglass skin had turned way too fuzzy), but they threw away the wood before I could see it.
Over at the Yahoo Chalet forum, I have a photo collection of my fixes of the cabinets. I took apart the passenger side one inside the interior, but reinstalled it as a complete unit, as seen in the pic below.
