I would spray some Kroil Oil or any penetrating oil, let it sit for a half hour, try again.
You can try by putting two drill bits that fit tight in the holes, backwards, and using a screwdriver put it between them and try again. The one I tried, the holes were the size of a 4 penny finishing nail, I think .073.

I know Midway sells one "Firing Pin Disk Remover" center to center pin measurement is .330

David