this is a relatively easy repair--my neighbors did it for less than 2k in san diego where everything is more expensive than anywhere else in boating..lol....the dish / step for the mast corrodes and swells cracking the hull---go get the dish replaced and have a great boat!!!!! myneighbors replaced the aluminum dish with stainless steel lol..now they have a consideration oif dissimilar metals to consider......aluminum lasted 28 yrs--why not just replace with same?? why reconfigure the boat making the mast much more expensive--will need to be replaced if keel stepped--is too short for that--needs the length of the cabin house roof to the keel added to what you already have------just replace the dish, reglass and possibly recore at the places where the water has been..inject the rest with epoxies and finish the houseroof and be done with it?/ the neighbors did that for less than 2000 us dollars at knight and carver .......
mine should be ready for this soon--is a tad newer at 1979......