you could use a chainplate type system. These are very important on monohulls, but here is a pic (from a monohull, but you get the point-http://www.semyan.com/GataLuna/Images/Dscn0095.jpg ) through bolted to the inside of the hull with lots of epoxy/glass/plywood backing then there wouldn't be that much pull on the repaired top of the hull.