I'm the new owner of a 1975 Cape Dory 28, possibly hull no. 30.
I've been doing a complete refit including a good bit of fiberglass work, a complete rerig and new systems for cruising. The boat is in pretty good shape structurally and internally but unfortunately a lot of water migrated into the deck and wreaked a bit of havoc. I was very impressed to find that virtually all of the factory installed deck hardware was still bedded and dry after all these years but someone down the line did a much more slipshod job and I've spent quite a bit of time making up for this. I'm still working on replacing the chainplates which this water completely rusted out.
Were the chainplates on other Cape Dory models this strange? Mine are just large hunks of mild steel with rebar welded to them in spots! Odd as it is it seems like it would be a strong design but it's not a good sign when you can pick the steel apart with your fingernails.
Anyway, it's been a lot of work and we're still not in the water yet. I've been very lucky though to have a lot of help from a couple friends and my father who fancies himself something of an expert on these things. It has been fun learning how to fix boats on a Cape Dory. My 28' is so simply and durably constructed that I feel comfortable working on any part of the boat, even as a beginner. I figure if she's tough enough to have survived all these years so well I should be able to get many more out of her.
I've some catching up to do but I'm documenting all the work we do on a blog herehttp://www.sailfeed.com/paul-calder . It's been a great resource having this site to browse through and I'm hoping this stuff will be useful to folks with similar problems. I certainly found the page in these forums on chainplate replacements invaluable when working on mine. I'm sure I'll also have questions as things progress.