I found a very small (dimensionally) 5000 BTU unit at Walmart online for $144. Best price I have seen for years and the size and weight were great so I headed over to pick it up. Got there and it was on rollback for only $100. What a deal, that's just about 50% less than I expected when I first started looking. Even better, it's black and will go very nicely with my white and black camper.
Thoughts on installation:
cut a hole just big enough to slip the unit in from the outside in, once in position then add the top and bottom rails to the AC case and from the inside add wood to build up the window like lip that fits snug in the rail channels. On the outside I'll get some 1.5" angle (black) and frame around it.
Of course the water proof tape, butyl etc for the opening and between the angle and the camper shell, then neoprene between the angle and the AC cabinet. I'll fashion a cover for the unit for while in transit or storage out of ~2" rigid foam. This will have a seal on it to mate on to the cabin wall. No bugs allowed!
Thoughts on this approach? This way I think I can just leave myself with less than 1/16" gap or less to deal with. Especially interested in hearing from folks that have installed one in there cabin wall, what would you do differently and what are you completely satisfied with? This unit is only 12.4" deep and weighs only 34 pounds.