Get lots of cobalt drill bits. You're gonna need 'em. Last time I drilled one out it took about an hour and I went through three 1/2" bits. Start will a smaller bit and work your way up. Have a vacuum handy cuz metal chunks fly everywhere.
As someone else mentioned, go to a GM dealership with the VIN and proof of ownership. They will probably be able to cut you a key ( less than $10)
DO NOT DRILL IT OUT, its a waste of time
the cylinder can be removed and replaced.
youll have to remove the panel around it to get in there so you can remove it. even if you drill it out, it would have to be removed
If the ignition key is the same as the door key you can remove the lock cylinder on the passenger door (less wear than on the driver door) and a locksmith can make a key for that for about the price of a new lock cylinder.
If you try to drill it out, forget about the key hole. It has to be removed by exposing the anti-tamper screws that hold the cylinder. If you attack the key hole it will not be drivable until you drill out the screws anyway. Your 1991 Regal has one of the GM passive anti-theft systems (PATS): Passlock or Passkey/PasskeyII.
How are you planning to get past the immobiliser as a screw driver will not start the car?
Check with your dealership and see if they can make you a key by using the Vin number.
I have a 91 buick regal GS. I lost the keys about a week ago and really need to drive the car. I can't get a locksmith or a mechanic to help me (poor college student) so, I need to start my car with a screw driver. Do i just take a drill bit to my key hole and drill it out? What size works? Is there situation where this wont work? I know its gonna ruin the ignition, but i just want it to drive, the car is nearly dead anyway..