how to change keyswitch
Ditto what he said. I just took apart two steering columns so the switches and turn signal cams could be swapped out. It is a pain in the wazoo, so you want to eliminate any other possibilities before tackling the switch. And it is true, if the lock cylinder does turn, it is not the problem. All the lock cylinder does is rotate a pin protruding from the end of the ignition switch.
Jerry