In the last build I did, I kept the rivit holes the same size and drilled holes through a couple bars with holes the very same diameter and bolted the whole thing together. That worked, for that one gun. Any other gun you try to do with that jig wount fit. I ended up drilling the rivit holes in the receiver larger and drilling larger holes through the bar. The holes through the bars are larger than the holes in the receiver to allow for adjustment. It relies on the pressure created by the larger bolts to keep everything still.
Installed blocker and opened up grip slot. Then welded it together. I love welding in the winter. You don't have to stop as often to let it cool down
