I too had butt sag with the Amerigo I had. When I gutted the it for refurbish, I discovered the problem. It had 2"x4" laid flat on the floor. Not on edge, but flat. As I recall, there were four of them. They were bowed from age, just hanging too long. Of the top of the walls, each side had one 2"x6" or 2"x8" on edge. These two also supported the rear overhang. My problem there was they both suffered from dry rot. I considered running a 2"x4" steel tubing frame under the TC. If my memory is not failing me, I would have run it flat to the overhang, down and to the rear. It would have been gusseted. On further inspection of the fiberglass roof, I saw thousands of pin holes. So, decided to abandon the project.
Wayne
