Re: please help.. locking screw is stuck..
You might try using the best fitting screwdriver then tapping on it with a hammer. Don't beat it to death just give it a few sharp raps with the hammer. Sometimes that will help break a seized thread. If that doesn't work you might have to resort to drilling the head off of the screw. If you have to do that then try to leave enough thread to grab with needle nose pliers or vice grips. A replacement screw shouldn't be hard to find at a good hardware or auto parts store. Good luck. Let us know how you do.
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