Mark Goodall wrote:

> Thanks Mopar Man, how do I know I've got the fan polarity right?
> Blowing toward the engine?

Well, first of all I would expect that one lead of the fan motor is
already connected to ground - because there's no need to switch BOTH
leads of the fan motor - just the hot or +12V lead.

If that's not the case, or if you can't identify the switched or hot
lead, then yes, the fan normally pulls (or pushes) air from the front of
the car through the radiator towards the engine block.