Please excuse an idiot question!
I have a very nice UW deck watch in the usual RN box - this particular one has a stainless steel double bottom case, with glass, and no broad arrow or HS2 marking. Serial number is 120521 - on the face, the case and the movement. I have an idea that these stainless steel double bottom cases were intended for submarines, in the pious hope that the case would offer some magnetic shielding, but would welcome thoughts on that idea.
It needed a new staff when I bought it, and it now has one and is running very happily but gaining more than a minute a day, which I think very nice deck watches, recently cleaned, ought not to do, and I would like to move the snail cam regulator.
What is the best and safest way to do this?