I have done the Conshelf pin trim thing and have also found a couple of regs (MR-12s, Triestes and Titans) that already had the AMF/Voit to USDseat conversion done to them. I disagree with some divers saying that the Trieste regulators don't breath well as configured. I have three of them, put new repro silicon 2nd stage main diaphragms from Rob at the Scuba Museum, and all breath great. The key is getting that new silicon 2nd stage main diaphragm in for better breathing effort. Just tweak the IP (135) and for me, hair trigger the 2nd stage lever a bit and they breathe like any modern single hose IMO.
I've heard and I am tired of the whining argument about "But its 2nd stage main diaphragm is too small, wah, wah, wah etc. ad nauseaum". When you think about it, the 2nd stage diaphragm is not any smaller (by much) than the Titan II single hose 2nd stage. That Blue label is a keeper, by the way.
The MR-12 is a good source for possible 1st stage parts replacements if your HP orifice is kaputt in your Trieste.
"Where'd ya get that ol' thang, don't cha' know them thare things ill kill ya!"
Live From the Red Sea,