Ignition switch problem or ??

93 C4 automatic, sometimes when I turn the engine off the ignition switch will not turn all the way to unlock position so the key can't be removed. It jams between off and unlock so it can't be turned either way. I have to keep twisting the key and the wheel until it finally turns. Is this a the ignition switch or steering wheel lock? Or something I am not doing right? Just bought this and never had a Vette before. No owners manual came with the car. Ordered one and waiting for it to arrive.
This is my first post so don't be too hard on this old man please.

There may also be an interlock between the floor shifter and ignition lock cylinder. If the shifter is not in the PARK position or the switch there doesn't sense that, the solenoid in the steering column will not allow the lock cylinder to reverse to the LOCK position.

It's similar on the B- and F-Body cars, not just the Y-Body platform.

There may also be an interlock between the floor shifter and ignition lock cylinder. If the shifter is not in the PARK position or the switch there doesn't sense that, the solenoid in the steering column will not allow the lock cylinder to reverse to the LOCK position.

It's similar on the B- and F-Body cars, not just the Y-Body platform.

Thank you, I didn't think of the neutral safety switch. Will check that.

Found problem was a defective ignition switch, replaced with a non-vats unit.