From the rear, the left crown that has no boss and is rivoted to the pulley and drives the left wheel, all these free wheel on the axle.
The right crown is fixed to the axle and drives the right wheel.
The FAAS gear runs freely on the axle.
There are 3x 80 pitch pinions inside the FAAS gear.
These spider pinions are soldered to a one off custom made boss that houses the 3 cut down motor shafts that locate the 3 pinions and the outer part of the FAAS gear (looks like a ring gear) is soldered to this boss. - Dave.