I had a 77 that I bought in 97. Good little boat very well built as were all of the CS s. I had the same moisture problem where the wiring went thorugh the deck. Not a big deal with these boats as the outer skin is strong and even if the core is gone there is no flexing. They are a very sound design but a little slow. On mine with the 8 hp I could only get 3-4 knots motoring into a headway with some wave action. It is always better to sail.
Good Luck.
Gary