I owned a 1976 C&C 30 II for about six years back in the '80s. That is a great boat, we did a lot of racing with her and as long as we got the right end pointed forward, she did quite well. The boat is an absolute pleasure in a big breeze, very stiff. I think the only design changes during its life were raising the boom a foot in 1977 and switching to diesels around 1980. Be sure to get involved with the C&C email group, and feel free to PM with anything specific.
I wouldn't mind having another one some day...