the worm is treaded on the end for the spanner nut that holds the brake hub onto the worm. on the trust end there are 3 tapped holes for 3 hardened bolts and a lock plate that hold the thrust bearings on the worm.the thrust bearing cap applies pressure to the thrust bearing race that is adjusted by the plastic shim/gaskets. usually .002-.004" thrust end play. the ring gear lash/backlash adjustment is done with the eccentric bearing hubs on the spider typically its .006". alignment left and right is the shims on the eccentrics. these are standard tolerances for worm machines. and the reason there is not much adjustments is because the initial machining was precise. its not like a cheaper hollister- whitney machine where a rough cast is done and each component has a 1/4" of shim to make adjustments. each way has advantages. that little 22ct moves 3500# cars up to 500fpm. pretty impressive for such a small gear.
