Had thoughts of an angle attached to the scalar backside, and then a hose clamp around it and the throat. But what I did was:
I put some double sided carpet tape on the 'pads' that the throat contacts opposite the screw. I also sharpened the screw to a point so when in contact with the throat** the throat didn't wobble. **Minimal pressure and it held without distorting the throat.
Make sure the scalar is parallel to the bottom of the dish and the feed throat is aimed at the dead center bottom of the dish.
You may see improvements by adjusting the LNBF closer or further away from the dish. Watch a transponder on the satellite you're aimed at, look for maximum Q.
These 'tweaks' probably will also minimize, or eliminate, picking up adjacent satellites.
It may be a few months** before it's tuned and tweaked to perfection, that's OK as that's normal operating procedure with the initial tweaking of a BUD.
**An hour or two once or twice a week.