Well i've gotten the rear siding back on, not everything fit back exactly as i'd like but thats okay they werent hard fixes.
Notice that the siding on the side versus the back doesn't match up. I'm starting to think there was plywood or paneling on the back wall before i got it. Not a big deal as i'm just going to take a cutoff wheel and trim it up.
Here is the rear wall and passenger corner. Yes it needs a very thorough cleaning