Thanks for the suggestions. Thought I should post some results. I started with the intermediates as the 1x 19 was showing signs. The old chainplates were 1/4" x 2 1/2". I am replacing them with 3/8 x 2 1/2" 316 S.S. Although I think Bronze may have been the better choice. I bored the holes in a single
pass with a normal drill bit. Used lots of water
as suggested. 1 Drill bit has done all the holes. I resharpened about every third hole. That was too easy. Years ago I spent a fotune with cobolt tips, stepped the drilling and used words well words.
So now I'm working on my polishing. I wet sanded with 120 then 220. For buffing I started with a sisal wheel
and black compound and then finished with a spiral cotton wheel
and green compound. Its pretty good but I wish I could get more of the surface imperfections out. Any pointers on polishing? I have the 1x19 made up with sta-loks. Hopefully March will be kinder and I can wrap this part of the job up. You can see the crevice corrosion
in the old chainplate. Although not as bad as some glad I pulled them.