Stephanoo,
If balancing your cartridge on this tonearm is easier without the screw, there's still an easy way to fine-tune VTF WITHOUT moving the counterweight (which is very touchy and affects azimuth, as you know).
Get some O-rings sized to fit snug on the end stub. Slide 1 or more on behind the counterweight. This will make very small reductions to VTF but you can leave the counterweight alone.
You're making great progress,
Doug
If balancing your cartridge on this tonearm is easier without the screw, there's still an easy way to fine-tune VTF WITHOUT moving the counterweight (which is very touchy and affects azimuth, as you know).
Get some O-rings sized to fit snug on the end stub. Slide 1 or more on behind the counterweight. This will make very small reductions to VTF but you can leave the counterweight alone.
You're making great progress,
Doug