I went to Autozone and got some red wire (10 gauge) and a 30 amp fuse.
I ran the 2 runs of wire through the fire wall (down near the bottom you will see a gromet with a thick black cable for the hood release)
One wire from the positive post on the battery to the switch to a toggle switch back to the fan.
I tapped into the green wire (I don't remember if it was the light green or dark green) but it is the high speed on the fan.
The toggle switch I used is rated for 30 amps same as the fuse I used.
I did not measure the current for the fan, I would guess it would be around 20 amps since the wire chrysler uses is a heavy gauge.