OK, the key is beginning to become difficult to turn, sometimes won't budge at all. So, I decided to replace both steering lock and the tumbler. I've removed the kick panel, the instrument gauge panel and removed the bolts holding the steering column up. I'm using a small allen wrench to try and depress the steering lock release button with no success. It seems as though it is stuck. So, I read that perhaps removing the tumbler first might allow easier removal of the steering lock. Any ideas or thoughts are appreciated.

This on a 1984 300DT, BTW.