It fits!
The blue Powerflex bush is a nice hand tight fit into the torque tamer shackle. It doesn't fall out like the yellow bush does.
The Blue Powerflex bush is 57mm OD
The Yellow generic bush is 56mm OD
The shackle without the metal sleeve is 57mm ID
I assume from others posts the shackle with the metal sleeve is 56mm ID
Therefore, if you have removed the thin sleeve from the shackle order the larger blue Powerflex bush #2607K
If you have not/are not going to remove the sleeve then order the smaller yellow bush
Both sets can be ordered from Motobuild. The blue Powerflex one is more expensive so if you have a choice don't remove the thin sleeve.. Unfortunately, the Motobuild Torque Tamer picture shows the bushes in blue so probably best to contact them once you have decided which route to take..