I just wanted to say thank you to everyone for helping out. This past weekend I relapped and lubed the seacocks that are looking good, and fitted the new Spartan seacock which is perfect. I also took apart and relapped one of the other "good" seacocks and found that while it is the only one that opens and closes easily, it also has a badly scored plug
that is too far gone to make a seal. So, I need a new one there too. I am glad I checked before hitting the water
On the drilling front, I am all set. I got the appropriate bits (HSS) and have about 50% of the silicone bronze machine screws I need, with the others arriving soon.
I decided to drill through the hull for all the seacocks and fasten with the machine screws, covering over with a vinylester filler, bedding in the seacock and the screw with sikaflex 291, and using teflon tape on the through hull threads. Next year, when she comes out again for soda blasting, I will replace the through hulls and add fiberglass backing pads under each seacock.
Thank you all so much. I had kind of a panicky moment there, because I want to get this girl out of the yard and closer to me ASAP, without ruining or sinking her in my haste. Everything is corroded to the point of immobility which adds to the frustration. Each job that should take 20 minutes takes a day due to deferred maintenance
issues. It's frustrating.
With your help, everything I do to her makes her safer and better than before. thank you so much for all the wisdom and help.