woh, once you get the key cylinder out you should be able to turn with a screw driver,,,did it just do it or has it been stuck for a long time

 

 

 

did you spray lots of lube in it. wondering if it got some crud in it and had to work it out.

 

I had a similar problem on my 98GMC, it was stuck in the start/run position and the problem was in the key cylinder where the rectangle plate that covers the springs and tumblers. The plate staking finally broke and the springs lifted the plate just enough to lock the key in the forward position. Once I got it apart and replaced the assembly it fixed the problem.

 

I know I'm late but...
I have a 1980 z28 witz28n automatic tranny, if the shifter cand put the car into park all of the way, you will not be able to remove the key. I had this same issuex along with the previous owner replacing the lock cylinder with the wrong type, so it kept falling out.