First of all sorry for my bad english, not a native speaker and quite hard to describe technical stuff.
So, my problem is with the screws that attach mechs to the playfield, under the playfield. Some of them, when being screwed in, keep turning endlessly and do not hold tight. Basically the hole in the wood, filled by the screw, is damaged.
Unfortunately all four holes relative to a single mech are damaged in this way, so the mech no longer stick tight under the playfield.
How to solve this situation?