I have the same fans and diodes from Precision Proformance, I put them on last fall. Mine came with a wiring diagram that I looked for but did not find. My original harness has 2 wires to each fan. One is black and the other is black with blue. The red wire on the motor is connected to the black wire on the harness and the motor black wire is connected to the black/blue wire on the harness. The diode is inserted in the connection to the black wire on the motor. The diode is not attached to the chassis. One end of the diode has a tab which I used to connect to the harness. The other end of the diode is a threaded post to which I attached the fan wire.
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