Thanks all, very much appreciated!
Dave..., I just use a Lindsay universal engraver to remove background, basically making a bunch of parallel cuts. The cuts are made fairly deep, but it’s more of a low relief, not the deeper relief like on the cast parts. After the lines are cut, the area is then stippled with a stone set. I used to use a flat graver to remove material, but this is much easier, and after the area is stippled, all lines disappear.
If you can see it, the area between the “fingers” on the top of the design around the lower butt piece screw was removed in this manner. I didn’t stippled this area, however.
Thanks again,
Ed