Oh, I feel your pain....... I married a beautiful Nurse back in '75. She's been the biggest supporter of my "affliction for Rugers" and the occasional Freedom Arms.......
I have a couple of those 50th Anniv. Flattops, too.
The top gun is s/n 636 BKH-3 from '55. The other two are the 50th Anniv. examples with a s/n of 636! The only way I could have put these guns together was if I got help from the boys here at Ruger Forum. That's exactly what happened and I was so gratefull!
flatgate