1967 DS1: advice on cam cleat replacement? Plus...

Back seeking advice on 1967 DS1. I use it for 2 weeks, big family vacation, every 2 years on a NC barrier island where it is stored outside (I live in St. Louis). Needless to say, quite a salty boat by now. Next visit in a week, and original cam cleats are shot. Plan to pick up new Harken or similar before trip, but what to do with them?
1. Main cam seems straightforward--I think I can remove old and drill new holes on the plate where it is now to attach the new one. But if this is a bad idea, I'd love to know.
2. Jib cams are tougher, and I've seen at least 6 different methods of mounting them in these forums (deck, under coaming, cuddy lip, direct to cb trunk, custom bracket over cb). Little time for anything elaborate, so I'm thinking of just mounting them to the centerboard seats as shown here: https://forum.daysailer.org/tech_rigguide.php Is there a better idea? There's wood coaming around cockpit so deck mount might be tricky.
Here's a view of overall setup + closer up.
Can't tell thickness of sheets, but guessing 1/2"--if you think different, let me know!
On less important notes:
3. The metal rings that position the outboard motor (inside the well) are shot. Worth replacing? Not sure where to find, D&R doesn't seem to have them.
4. Easy way to add drain plug? Sounds risky from what I've read here and don't want to spend $88 on the D&R one, but... maybe just a hole in the right spot and a rubber plug that fits (+backup)? We don't use the boat much and it sits in the rain for 2 years at a time on a barrier island w hurricanes etc., and next time spars or other major item goes we'll probably retire it.
Thanks,
Dan
1. Main cam seems straightforward--I think I can remove old and drill new holes on the plate where it is now to attach the new one. But if this is a bad idea, I'd love to know.
2. Jib cams are tougher, and I've seen at least 6 different methods of mounting them in these forums (deck, under coaming, cuddy lip, direct to cb trunk, custom bracket over cb). Little time for anything elaborate, so I'm thinking of just mounting them to the centerboard seats as shown here: https://forum.daysailer.org/tech_rigguide.php Is there a better idea? There's wood coaming around cockpit so deck mount might be tricky.
Here's a view of overall setup + closer up.
Can't tell thickness of sheets, but guessing 1/2"--if you think different, let me know!
On less important notes:
3. The metal rings that position the outboard motor (inside the well) are shot. Worth replacing? Not sure where to find, D&R doesn't seem to have them.
4. Easy way to add drain plug? Sounds risky from what I've read here and don't want to spend $88 on the D&R one, but... maybe just a hole in the right spot and a rubber plug that fits (+backup)? We don't use the boat much and it sits in the rain for 2 years at a time on a barrier island w hurricanes etc., and next time spars or other major item goes we'll probably retire it.
Thanks,
Dan