Patience I have. I need to develop some skill with the file.
Marking the pin with a punch is a good idea. Will need to keep that in mind.
Also, the finish on the ejector was flaking off. I am surprised. All the other bits I have gotten from Wilson Combat have been good.
EGW or Shooters supply. I stopped using Wilson a few years ago.
And get a set of files. Use the round one in these areas for a solid purchase.