We to owned a C&C 35 MK III. Her keel was also longer than should have been. We had the opportunity to sail with one of the fellows who worked for C&C and he told us that as C&C was closing down and boats where being finished that whatever keel fit the stub that was sitting on the factory floor is what went on the boat rather that manufacture another when they were closing. I know this is a late post but we've been sailing and don't spend much time on the net.
Hope this helps oldsailor100