If you need to figure out the thread direction on the couplers etc, just remember this trick (it always helps me):
1) Look at the impeller and determine which direction the engine turns, the blade direction will tell you.
2) Remember that the motor/driveshaft will always be turning in the direction that tightens the couplers and impellers when power from the motor is applied.
3.) Rotate the part the opposite direction that it turns under power to loosen.