Installation Procedure for the PTO Adapter.  The overdrive shown in the following pictures is a front shift unit.

The rear bearing cap must be removed, exposing the spline shaft of the overdrive.  Four bolts hold this cap to the overdrive housing:

 

The adapter attaches to the overdrive housing with the same four bolts.  A new gasket is supplied:

The drive sprocket (See upper right corner of large picture at top) replaces the spacer on the end of the overdrive shaft.  The PTO drive unit bolts to the adapter: