Took some pics of my failed repair so that you can see the error of my way. First a pic of the plywood installed upto the wall - tight on the sides and gap of about 1" on end near rear door. Thought was to 'insulate' the plywood from leaky wall or whatever. Second pic is close-up of the edge - c-chanel was filled ithe 5/8 green treated (another mistake), caulked into place(yes, another mistake), and once that was done I placed the plywood in, fastened it down and put spray foam around the boarder to seal air leaks (yes - I know - now). Third pic is of fully clogged c-chanel. That caulk is very tough - unforatuantely it worked as adverised (tied removing some tonight). Four is a delightful representation of my blue foam belly insulation and a large perimter of c-chanel waiting for me.
Three and five also show the nicely rusted and bent elevator bolts.
On the happy side - the forum kept me from complete disaster. This is an easier redo than a failed monocoque frame AND shell. Once I pick up my nyloboard and get the c-chanel clean I wil post some more pics.