I have a 1987 300TD, and last week my mother in law went to unlock the drivers door, and pulled the whole tumbler out of the door. I could'nt believe it.
I have had no luck trying to get it back in. The tumbler has a little lip that looks like it should go into a little slot in the door, but I have not been able to make it work.
Here are some pics...
pic of tumbler
-- Thanks, Andrew