I've gone with HiViz FO sights on my 686-6 3", the NM 66 4.25", and the latest NM 66 2.75". To dwhite, thanks for posting your info about the stock rear sight height, that's been driving me crazy for a good sight picture on the 66 snub. I have ordered the .146 rear with white outline, and hoping this gives me a better picture as it did for you.
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