Note the screw runs through two "arms" of a U-shaped bracket. There is supposed to be just enough interference to prevent the screw from moving freely.
Remove the screw, and then take a pair of vice-grips and clamp the two arms SLIGTLY together to add a touch of interference. Then reinstall the screw.
Jon.
He is called 'carbking' for a reason. If you bend the U-shaped bracket together by a distance equal to 1/2 the pitch of one thread on the screw (carbkings 'slightly' reference), you should have what you need. I did it on my 52 twenty-nine years ago. It is the subtle things like this that make this hobby so much fun.