Thought the diagram was sufficient to show how they wire.
What is it that is not clear?
You take the red wire off its terminal
You take the black wire off its terminal
You then run 6 wires to the motor
2 of them connect to where it shows L1 and L2 that is power
then 2 connect to the red and black wires
then 2 connect to the stab connections where you removed the red and black wires
Now, you flip flop the red and black wire connections on those stabs and that is what changes the motor direction.
When you apply the power it runs which direction you have chosen by the red and black wire connections
As far knowing what someone wired to the motor, I cannot say without seeing them and knowing where they originate.