I'd leave the grips right where they are and not attempt to remove them.
I know the collector need-to-know if the grips are #'d to gun is high,,but at this point just simple observation can tell you they fit the frame perfectly and have the same look as the rest of the gun.
That they are very fragile material is not in dispute and I see that at least one panel has a hairline crack already on the bottom in the closeup pic of the ser#. I think the other does too. Probably leading to the grip pin.
Those gutta-percha/hard rubber grips can stick to the frame like they are glued in place with old dried oil and lubes.
Taping on them or the screw can leave you with a multi piece grip panel in a hurry.
The only bright side to that is that you can still probably piece the sections together on the bench and read the ser#.
It's not going to be for sale, so 'all matching including grips' isn't an immediate need-to-know.
Later on with some careful surgery, the grips can be lifted from the frame with patience.
Wipe the gun down with nothing more than a cloth and your favorite gun oil. No polishing abrasives no matter how fine, no buffs, no need to make it shine.
Removing any patina from the plated finish isn't needed nor going to do it any good IMO as far as preserving it or granting it any value.
What's the very first thing told to people when they have a patina covered piece,,don't polish it up,,don't refinish it.
It doesn't need 'restoration',,it just needs some preservation, appreciation and maybe some of it's lost history found.
You are lucky to have a family heirloom like this especially w/the connection in L/E.
Most get sold for beer money by someone in the family.
Just my 02
I think that pulling the grips was more to verify the N marked in the frame rather than verify the grips are original. That being said, if I were to try to remove them I would NOT use the "tap the screw" method. I'd remove the screw and tap the frame with a screwdriver handle similar to how you remove the side plate (not tapping on the grips) and see if they would vibrate loose. If not, I'd replace the screw and just send for the letter, which will verify the originality of the finish.
But that's just me.......
