Call Rudy Nickerson
Johnny, Give Rudy Nickerson of D & R Marine a call. You didn't mention the year of your O'Day 25, but you say that it has a cable. So, I'm thinking that you must have a 25 built in the mid 70s where the cable is mounted on a small winch with a crank inside the cabin on the table pedestal. I think that the centerboard on your boat is fiberglass and that you can use a braided line instead of the wire cable. Talk to Rudy about this. I'm pretty sure that he could tell you for sure. He has all the O'Day parts and could ship you a new pendant line for the centerboard. It will probably have a long flat shackle that can attach to the trailing edge of your centerboard. I wouldn't bother emailing Rudy because he doesn't answer a lot of his emails. Just give him a call. He's very knowledgeable about O'Days because he used to work for them. He bought out most of the boat molds and O'Day parts when O'Day went out of business. Good luck.Joe