my '85 ford f150 won't shut off even with the key removed
Seems like you need to change the switch as well as the lock...
As Joemom stated it could be the lock cylinder or the switch mechanism inside the column. Eventually it's not going to start either. The cylinder is not difficult to change and not overly expensive. Try that first. If the current key has a chip in it you will have to purchase the same type and have it programmed.
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