[undy]

To add on to what Rick said...

The one wire alternators will run about one to one and a half volts lower than the factory multi-wire units. That might not sound like a bunch but it will limit the peak speed that your fan(s) runs at. If you're cooling challenged with your ride it could be the straw that broke the camel's back...

I run #8 wire on all my "line voltage", non-control fan wiring. My relays from Hollister Road are rated at 60/70 amps. The Taurus fan on hi-speed will draw near 40 amps. You typical "100 amp" alternator will generate a paltry 25 -30 amps at idle, not enough to run a amp intensive large CFM fan for prolonged idling periods.