Showing the unattached DIY Redi-Mod ReDIY-Mod.

The cutouts are seen including the larger opening for the serial number markings. Also seen is where the dremel cutout discs cut longer than the opening. I really needed smaller discs that wouldn't over run the cut. Each corner of the opening was pilot drilled with a small drill, then enlarged with a 0.25" drill bit. That allowed the 0.25" bit to run through the prior hole. Using a punch would not quite fit the drill bit tip (such that it would run out) and if you bashed it hard, it would deform the metal. Using a pilot drill worked well to prevent runout. The cutout near the mag release was only 0.2" instead of 0.25" wide.