I am been made aware of a man who has a 1911 that has the serial numbers filed off by the original owner. He was afraid that Uncle Sam would not like him taking a pistol and of course he doesn't.

My question is, "What is the process one uses to restore the impressions?" I understand it is acid. Not my intent to touch the weapon and the present owner is a complete a$$. So I have NO motivation to help him!
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