there is a temp switch on the right head between cyls 6 & 8,looks like a the temp send unit on the left side.IF it is original it should be set a about 234 degrees F.
I have an aftermarket one,I think it set somewhere around 200 degrees F.
Bill , Thanks much for the quick reply and the info i was looking for. The car runs at about 200 degrees, so i was not sure when the aux. fan would kick on. I had pulled the plug apart on the side of the fender and checked it with a test light. There was power on both sides of the plug ( not sure what that ment ). Anyway thnx again for the help. Dave