The electric installation is easy, only you must follow the diagram:
Measure the voltage in both fan terminals, and write in a paper the values when the fan is turned off.
Turn on the engine and wait that the fan turn on and write again the news values.
Check with the following tables to see what is more like to your annotations.
If you annotation is like example 1 connect the yellow cable to cable 2
If you annotation is like example 2 connect the yellow cable to cable 2
You can optionally install a shutdown for the engine. There are many ways to stop a engine, the installator must be take care to choose the way that:
-The driver dont loose the brakes.
-The driver dont loose the direction.
-The driver dont loose the vehicle control.
A logical way is cut the fuel.