All is well. If you raise the deck, you lose freeboard.....the gunnel ends up lower in relation to your body. So raise the deck five inches....instead of being inside the boat at zipper height....you're now just above knee height. Not a biggee running around the bay.... but offshore in rough water...something to consider.Your existing stringers are good to go. Cut the tops off, pull the foam out....just as our new member has done on her '74. Foam is cheap...don't pay crazy money. The only closed-cell you'll need is inside the stringers. Block foam is fine and IMO preferable to lay in the hull beneath the deck, outside the stringers. Don't apologize for wordiness. If that's how you fly, good by us. I myself just like to post a lot This is going to be a great experience for you. Trust the members, a lot of knowledge here....no worries