Originally Posted by SnoSheriff
That rust is on the rear wheel well. From the rear of the camper I can only see 2 frame components. One of them is directly under the picture that you mention. The right one is in the 3rd group of pictures on the right, 2nd from the top. Now I'm off to the 'frame forum' for some more education
Maybe someone else will jump in and confirm or disagree with my above rust concern.
The photo below the rusty photo shows normal surface rust.
The other frame pics look OK, but the outriggers rust out first. Unfortunely for the most part they are hidden above the belly pan. Maybe you could get a peek at one or two from that hole in the belly pan.