Silentfaith, Your project sounds like a lot less work than someone else's job. Was it Bucky or MangoMama? I'm curious if tightening the bolts down made your interior roof buckle up from the airspace between? I don't really have much of a sag issue on mine except in one small spot. It makes cleaning the top of the pilothouse a little harder but it's also been an excuse to not mount solar panels due to weight concerns. Photos would be great if possible.
Thanks for posting this and congrats on your purchase of Velvet, I've seen photos of her she is a fine boat.
Captgrail