The problem might be the switch-- the cylinder does not have anything to do with the ignition part. Pull the lower cover from the steering column. The ignition switch is right there--it is held in with a couple plastic tabs-- just pull it down. Then see if you can turn the cylinder.
The key cylinder turns a gear, and that turns a gear in the switch-- to turn ignition and starter on--or off.
The switch has a detent in the on position, so turn ther cylinder to "ON" when you insert the switch back in. That way it will be indexed correctly.
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