how do i wire aftermarket fan

[airforceone]

to the existing wiring harness?

 

[airforceone]

has anyone done this? or do you know which stock wires do what?

 

[buickboy]

If it is Ramchargers dual fan they have the adapter to plug into the factory harness. If it is a SPAL dual fan Caspers Electronics has the adapter for the factory harness. Single fan-uh, sounds like a 30 amp relay and some manual wiring.
Mitch