Progress!!
Drilled out the UHMW pucks
It was snowing outside and I had nothing better to do, so I got a wild hair and switched the machine over to TIG. Probably haven't tried/done TIG for ~2 years or so.
For whatever reason I couldn't figure out/get the footpedal to work so this is just with the trigger on pulse.
Tried to TIG on a couple of spots on the inside of the brackets, but it was a PITA, so I will MIG weld the inside next time I am out working.