Ignition Won't Turn Off

[E9project]

I'm new to the forum but have owned my 02 Boxster S four years. Overall it has been a great car to drive with only minor repairs. My current problem that I'd like some help on concerns the ignition. A few weeks ago my AC started acting funny, the fan would come on but vary in speed indication, no snow flake, no cool air, etc. Shortly, there after my alternator light came on. I suspected my original problem was the ignition switch since turning it had become progressly harder in recent weeks prior. I also thought that the switch going open with the car running could have crashed the alternator regulator. So I order the replacement switch and a new alternator.
The switch that I pulled out did not match the one sent. It did match the 2004 part so I guessed that my switch assembly have perhaps been changed out during warranty before I owned the car. I bought the 2004 switch installed it and the new alternator.
My biggest mistake was deciding to take my wife to lunch in my now purring red Boxster. Everything worked as it should other than the airbag light from removing the passenger seat (has to be reset). After driving 40 minutes or so, I pull in and turn off the key. I also let the clutch out after pulling the key, not noticing that I was holding the key out of ignition and the motor was still running. Does it sound to you like the actual key assembly is busted? The key turns free like nothing is moving but the key tumbler. It does not make that mechanical chunk when the key is removed. Any ideas are appreciated. Fortunately, my other foot was on the brake and the engine died. Then all the lights in the light bar are lit up like the key is on. The steering wheel is not locked.