1999 Cavalier Z24 Stuck Key

Hello folks, I have a '99 Cavalier Z24 with a stuck ignition key. Can't turn the switch off. Already checked the tumblers and the lock cylinder mechanism. I'm thinking the problem is with the steering wheel lock mechanism, or transmission. I've noticed that the steering wheel lock pin is not engaging. Any advise on the location of a cable to check from the transmission or on the steering column will be appreciated.

Here's what GM says:

Park Lock Cable Removal Procedure

Caution: Before servicing any electrical component, the ignition key must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures. If a tool or equipment could easily come in contact with a live exposed electrical terminal, also disconnect the negative battery cable. Failure to follow these precautions may cause personal injury and/or damage to the vehicle or its components.

Disconnect the negative battery cable.
Remove the console. Refer to Console Replacement in Instrument Panel, Gauges and Console.
Remove the left sound insulator. Refer to Insulator Replacement - Instrument Panel (I/P) in Instrument Panel, Gauges and Console.
Remove the knee bolster.
Loosen the lower steering column bracket bolts.
Lower the steering column.
Place the transmission shift lever in the P (Park) position.

Important
Do not proceed to the next step with the key in any other position than the RUN position.
Turn the ignition key to the RUN position.
Insert a screwdriver blade into the slot provided in the ignition switch inhibitor.
Depress the cable latch. Pull the control cable from the inhibitor.

On a side note, did you remove the ignition switch to see if the key turns then?

Thanks for the information. Yes, I completely removed the key and cylinder mechanism from the console. The cylinder turns freely. The hang up is in the steering column.