Dave, I don't know for sure but think the floor is 5/8". Mine is swollen just about everywhere you can see an edge. The worst is up front under the bunk where my front window has leaked over time all the way down to the floor. I have the leak stopped for now and plan on replacing the floor some day when I take the bunk out to do a front dinette mod.
As to the cabinet doors if you are replacing them then the thickness of the originals does not really matter as long as the hinges work, if you are reusing the original hinges that is. Not a lot of information but maybe the bump will get this back where somebody that knows will see your post.