At a show this past weekend another dealer sold a Ruger Mark pistol to me that is in need of a lot of refinishing.It was scarred badly on the outside by rust or something to the point that at about 10 feet away it looks like it is engraved. I know that I'll do a blueing job on it I just don't want to ruin any of the lettering or give them that rounded look that most reblued weapons have. Any ideals on how to keep the letters sharp?