I just got a good deal on a slightly rough "shooter" 37 Airweight. The very top of the aluminum frame had alot of the bluing worn off, and it looked like someone just blobbed on some touch up cold blue. It was even a little sticky.

When I cleaned it good, alot of that came off, leaving the top fairly shiny. Is there any good way to touch it up, or at least darken it up some. I know that the cold blue touch up does not completely hide blemishes, but will anything work good enough to darken up the top a little?

Most of the cold blue I looked up on Brownells does not mention aluminum. The Formula 44/40 does say for any non-stainless steel guns. Anyone have any experience touching up aluminum?

Thanks,
Josh P