Bits ordered!
I have about six 1/2” bits in the last one semi worked. I got it through, but all of the bits are inly good for wood or soft metals now.
I knocked the stud in with a brass hammer. It wasn’t too difficult, so I’m thinking I may do a small weld on the back, to keep them from spinning…
Since the back of the flange has a slight curve to it, I ground the area around the hole flat. Going forward, I will only make the flat spot just big enough for the head of the stud.