@fred-y Thanks for this idea - it seems to work. I made this:
using the two holes on the motor side of the extruder. This leaves a nice gap on the molex connector side for the plug to fit properly.
This is how it looks in situ:
I am using the default sensitivity on a v3 smart effector, and found that it needed an extra -0.04 on the probe offset. Seems to work well though - a 19 point G32 gave a 0.010 fit.
The mount pictured was printed with the new setup - I was fine tuning the thread diameter - 12.3mm was good for me. I havent pushed the new setup yet - seems promising though.