I can follow your question, but I am concerned that the new hull you bought has been repaired where the side stay attached. If that is the case, what damage was there and how strong were the repairs made. This seems like a very high stress, important part of the hull. If you drill it out and get it to work, how long would it last? I wouldn't ever have confidence in it.
Like you mentioned, originally, it is just a rod with a threaded hole in it sitting under that lip. In fact, I have often wondered how this can be strong enough, but rest assured that thousands of boats over a 40+ year history have proven it generally works ok.
I would be very cautious with the new hull, maybe even look for another.
Sorry to have to say it.
Good luck, and let us know what you end up doing.
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Steve
2017 Hobie 16 "Cayman" sails 114795
1985 & 1973? Hobie 14 "Sea & Ski"
