I have always used gyros with the GT Block aka Mallet stem.
Now I was going to use a ACS Pro Rotor with it but I find 2 problems:
1- The length of the GT shaft... It's pretty short, It can probably work but its at the height line limit.
2- The hole drilled through the stem is not in alignment with the rotor... why? Is it drilled for another rotor? Spintech? I don't know...
So what do I do? give up with this setup and use a gyro or find that small adapter that goes on the pots bolt?