Notching an AK-47 Safety Selector Lever for Bolt Hold-Open

Next I washed it with dish soap and water, thoroughly rinsed and dried it, and then applied Birchwood-Casey Perma Blue cold blue paste to the entire piece. This blued the raw steel where I made the cut, and touched up some bare spots where the bluing had been rubbed off. Applying the paste to the whole piece eliminated dark spots where the touch-up blue was applied. Then I wiped off all of the paste after I let it work for about a minute, and wiped the lever down with a good coat of Militec-1.