WHAT NOW? How's this come off??

Absolutely not........You'd ruin the column shaft...........If you simply put a drop or 2 of good cutting solvent on the "sunken" end of the pin and tap it a few times to get it in there, then hit it with a proper sized punch, it will come right out................. No drilling necessary...........

If the original pin is IN there, you must drive it from the SUNKEN end, NOT the flush end...........The flush end is wider, and you'll just beat your brains out for nothing. 8)