Those serial numbers were either on the front of the grip or on the left side of the frame under the grip. The grip screw may have to be drilled out, but I would try using a small screw-driver bit in a drill press chuck first. Pad the drill press table, then chuck the screwdriver bit into the chuck and hold the press down so the bit is in the screw slot, while turning the chuck by hand (no power). That will work on almost all buggered screws.
Jim