I recently bought an 889 and have been thinking about removing the black coating too. I tried a small area and found out that it buffs off pretty easily with Scotchbrite, at the expense of some slight spider web scratches. They're very fine, I can probably polish those out easily later. Might do the whole thing later, haven't decided yet.
FWIW, I couldn't find the thread TLC mentioned, but what I did learn from others was Naval Jelly should be treated with care if you decide to go that route.
BTW, welcome to BF.