You've got your mounting screws in upside down...
View attachment 1347204
No, that's the correct way, with the nuts on top. The nuts can damage the cartridge body, so it's best to have them on top of the headshell. Also gives much better clearance with the screw head on the bottom.
When using a Technics headshell, the nuts on top fit perfectly in the slots so they don't turn, much easier to mount.