Putting together a fish for some racing and as I started working on the hull my sander started bogging down in an area right under the cockpit. On closer examination I found what appeared to be some lumps - 6 on each side of the keel. It seems that the dolops of glued used between the cockpit floor and the hull gets really hard over the years (boat is a 73). Coupled with the pounding the bunks on the trailer have done on the part of the hull - I NOW HAVE LUMPS. They are about a sixteenth to an eight high. Short of grinding and fairing any suggestions?