Attempt #2 is coming back together, I just have the driver's side wall and floor to reglue in place:
I'm making it stronger this time, using some extra bracing behind the walls and some five min epoxy to hold it all together. The Bondo work on the roof is done (I used enough hardener this time!!) and after the other wall and floor is on, I'm going to sand the rivets off to make everything smooth as most of the real ones are and more Bondo S&G putty to smooth everything together. Hopefully, the temps here are going to be in the low 60s by the end of the week, so I may have the truck in primer by this weekend!
What kind of body filler did you use?