Hi Steve,
Thanks for the reply. Yes, the floor & frame rails of the trailer all sit flush with each other. A picture of the trailer I am considering is below. I have seen a couple folks that had custom trailers built as the basis of their build in aluminum with a flat deck of alum sheeting and they just bolted plywood right down on that flat metal deck sealed with butyl tape, but since diamond plate could leave tiny gaps between metal and plywood where moisture could seep, that's why I was concerned of how you could protect from that because otherwise this trailer looks like a great platform for the build.

- Trailer.jpg (31.2 KiB) Viewed 332 times