Installing Hairspring Into Regulator: Longines 12.68 with "Shock Resist"
To clean and inspect the jewels in this "Shock Resist" system you need to remove the balance wheel and take out screws that are underneath. Now that I have done my inspection, I am contemplating how to reassemble and found that the space for the hairspring to go into the regulation arm is VERY small (see first pic). I have seen on more modern mechanisms a way to turn the outer stud to adjust the amount of distance between the two pins, but this doesn't seem to have that option. I thought maybe I could put a small pin in that hole and twist it to open up the space a bit, but I see no indication on the bottom that the piece has ever been moved (no scratches or scuffs under the larger pin). Do I just have to be super precise when installing it back or can I move that larger pin with the hole in it? I didn't want to force it and potentially break it. TIA for any guidance!