I am using this in my rotary powered aircraft. I am only putting 200 HP
through it. Will need machining of clamp plates to transfer torque.
This also fits well inside of a Mazda bell housing.

The way  the coupling works is the flange bolts to a "flywheel" and has clamping ring on the other side of the flange which has holes in it for bolts.
The center I copied the compression rings one on each side of the opening in aluminum and made up a internal splined center out of 4340 steel. The clamping bolts for the compression rings also attach the steel adapter. The PSRU input shaft has external splines which mate with the steel adapter. The input shaft then continues into the clutch pilot hole. The rubber coupling sees only torque no radial loads. The rubber coupling is made like a tire with internal fabric cords laid at a 45 degree angle. The cords actually carry the torque not the rubber. But the entire coupling is some what flexible in torsion.

I have not flown the setup but do have over 50 hours on a test stand of running the engine,coupling and PSRU with no discernible degradation.

Chris Smale