SHOP TALK!!! how to defeat a stripped screw head without losing your mind<br /> by [[Typewriter Justice]] on Youtube
To help remove a stripped screw head, hit it with Kroil or a similar penetrant first. Then with a screwdriver, punch or similar tool, give it purchase on the right hand side somewhere and give it a nice whack with a hammer. This should turn the screw enough to move things along.
Charlie attributes this trick to Dane Bailey (August 19, 1932 - April 21, 2019) of AAA Typewriter in Birmingham, AL.