After you order a new switch from the Dealer, then you can consider removing the old one.

Matthews had someone take the lock cylinder apart, toss the broken bit (it is the steering wheel lock or ignition lock part), put it back together and drove the car. Be careful with the security ring.

I would drill a small pilot hole, enough for a punch to get purchase, and punch it counter clockwise to get the break off screws out. Once it starts to turn it spins easily.
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My back feels better when I sit in a Volvo seat