Oh the forget to put the anti rotation device in placed trick.
IF it at the electric clutch one wire is ground and the other is switched 12v. Got to be careful reconnecting as some clutches have a built in diode that short out if connected wrong. And schematic does shows this diode being there.
The +12 vdc lead for clutch goes to terminal "E". On the PTO terminal "B" should have +12 vdc when the ignition switch is in the run position.
And PTO switch pulled to on position.

Provided you have an PTO clutch with a detachable connector then following should help in connecting up the PTO wires at the clutch. Note red is the +12 vdc wire.

This is Rotary 10-12923.