There is a crack on the port side of the Cabin top and it appears to be rust leaking out of it. the location is in-line of where the mast sits on the Cabin top. In the Cabin, there is a rib running from side to side and it looks to me to be a structural support for the Mast. My question is, is there a metal brace in-cased in Fiberglass? From a repair standpoint, is it soild metal to the top of the Cabin skin, hence no core material? If it is, I was thinking that if I get it dry, and seal up the leaks, repair the crack, I'm done. Has anyone see this before? Any suggestions how to repair this right will be greatly appreciated.