Howdy! I'm doing some modifications to a glass boat. It is old and seriously worn. No idea how old, what it is made of, ect, but it looks to have sat in the sun for about ten years.

I'm wondering if I can just sand whatever resin it is down and bond to it with epoxy? I've gotten conflicting answers from credible experts, which is why I'm asking more here. Someone suggested that if it's vinylester resin, the epoxy won't bond.

Here is a photo of the inside of the boat, is that kevlar? how can I tell?