TOPIC: 28ft 1973 Fiberform something-er-other

I just purchased a boat on craigslist in the SF Bay area. I'm trying to get info on it, but I'm having trouble finding out exactly what it is! All i have is the pink slip and some info that the previous ownwer gave me (I wasn't the original owner - I can't imagine how many before him).

The pink slip says the Yr. Model is 1973. It's 28ft with a 10ft beam. Anyone have any idea what it might be? Sorry I don't have a great picture.

Any way to track this down with a CF number or something else?