My '94 s10 pickup's key is stuck

If you can turn the key to the start position, and it returns to the run position I doubt the issue is with the key and tmbler assembly but rather with the switch itself. Easy check is remove the switch and see if the key then returns to the lock position. The other possablity is the "rack and pinion" assembly located in the left side of the column has worn out. The pinion is what the tumbler assembly connects to, it moves the rack which is conected to the rod that is connected to the switch at the base of the column. I've just never seen a tumbler assembly do what you are describing. As for safety, make sure the battery is dosconected. And yes you can remove the tumbler assembly with out it in the lock position. You should not have to mess with the steering column support bracket at all. The ignition switch can be replaced with the column in place.

Whitelightning

Okay, I got the steering wheel off (easy) and the lock plate, well, the removal instructions were incomplete- to be kind. There's another plate- that you don't compress, you unscrew it- never mentioned or shown in Chiltons or Haynes. Worst of all- not in Mitchell's. The new key cylinder fit fine. MARK