Now I get it, the clamp screws have both left and right handed threads on the ends.

I'm new to this forum so a little about myself: I've been building basses for about 15 years. You can find my work under name MPU in Talkbass. Now I'm making a Parker Flyish guitar https://www.talkbass.com/threads/winter-build-off-2022-mpurker.1545407/ I have trouble understanding how the height adj...