I've got a Baretta 92FS in stainless, so the frame is some sort of silver coat. When the gun was first purchased over 20 years ago a lazer sight was mounted (i.e. glued) to the frame. the sight is long gone but the frame still has glue on it. It is very hard like epoxy and doesn't response to the normal solvents to remove glue. Any suggestions on how to get this off, or am I just destined to live with it or have it scraped off with the frame having to be refinished?