Update. Gun won't be ready until next week. New bushing(s) arriving on Friday or Saturday. They are staked on the backside. He did try drilling out the screw. I don't know if he bunged up the threads on the bushing, and honestly, I don't care. My conclusion was that more likely than not, the bushing would have to be replaced. So the fact that I was right makes the delay and minor extra expense reasonable.