I bought this 1988 four winns 245 this spring and it had a keel guard on it which was partially loose so when we pulled the boat for the winter I pulled it off and the gel coat on the keel is missing for about 2 ft by a inch and a half wide, what is the best approach to fix this problem, we do not beach our boat so I was thinking to put gel coat back on or some type of a epoxy, need some advice