Shipwright,
Pretty hard..your choices of drill bit material is sort of limited. Most bits, as I am sure you know, are just High Speed Steel. The new rage is to coat them with TIN or NCTIN or TTDTEGBVD or Cobalt or whatever. This is still a coating over a HSS bit!
If you just won the lottery, you could use solid Carbide. Unless you held the steering arm in a fixture and used a drill press or mill to attack it, you would end up with a broken drill bit.
Isn't the steering ball pressed in and swaged over on the back. Could you grind off the swage and press it back out?
Another option would be to heat the ball red hot with a torch and let it cool. This would anneal it. Then cut it off with a small cutoff wheel and drill through the center of the remaining piece.
These steering components are probably case hardened for wear ability, but they certainly aren't through hardened. They are TOUGH, but not BRITTLE.
A coated drill bit with coolant and a slow speed would probably also do the trick. I will bet there are hints-o-plenty waiting in the wings.
Stuart
