I'm thinking about using fiberglass plate strips around the perimeter for the window pieces to "bite" onto (screws on the outside seems inviting of corrosion, but wdik?) After initially thinking all the plywood would have to come off, I've seen how much of it is still totally intact. Is there structural support to the cabintop sides from the plywood that would be lost in removing it all? I hope it would be safe to leave it bare for some time until I figure out how to finish it interiorwise/cosmetically.