Last Friday evening, I had to leave my engine running at a christmas party because my key would not return to the off position!
After reading this thread, I proceeded to remove my tumbler too but because I could not line up the two holes, I ended up removing the knee bullster and that gave good access to remove the whole unit!
Once out, and lucky it stuck where it did because you cant unplug it from the harness unless the key is switched to ignition on position (strange!)
After discovering I could turn the key shaft from the other end, I could now get the key out! Later, I positioned the key so the holes lined up and tried and tried to remove the tumbler, no luck!
But now with the key operational, I loaded the hole unit up with 90 wht. oil and it turns freely through all positions, so I ended up putting it back in and so far it works OK.
Incidentally, if you ever need to remove your VDO cruise amp, it's real easy to get to with the knee bullster removed, and removal of the bullster is easy and quick! And that goes for the buzzer too!

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