I have a 69 cougar that had the wiring harness ripped apart… Not by me! I am now tring to re-wire my Cougar with a painless wiring harness. So far so good, only two issues remain. 1st: I can not figure out how to complete the wiring of my heater blower motor. It is a 2 wire 3 speed unit. I have wired the switch and the ground wire, but where do I hook up the power wire and how do I connect it to the resistor? I have the shop manuals but they are’nt all that clear on this point.
2nd: Has anyone wired in a 1 wire Altenator, a real one wire with only the power and ground posts available and with an internal regulator, in place of the original externally regulated Alt?
Any help, especialey diagrams, would be wonderful! I have lost more than a few hours sleep over this… 
Hugh
My experience is that the Painless isn’t a good match for a Cougar, but you are in deep by now so here goes…
The fan speed is controlled by the number of resistors that the supply voltage passes through. So in the low speed position the output of the switch goes through all of the resistors, in the second position it goes through a single resistor, and in the final position, it bypasses all of the resistors. I have no idea how the painless system is set up to accommodate this.
If you are not in too deep, you might want to consider buying an original harness that is in decent condition. A perfect harness with no splices can be expensive, but a harness with just a few minor splices can be really cheap. Call Lin at WCCC and he can give you the run down on which one you need and prices. Every Cougar came with a wiring harness so every car they scrap potentially contributes a harness to their stock. The perfect ones go to the concours guys for big bucks, but the just less than perfect ones are really cheap. Cougars have a lot of unique features like sequential lights, that are very difficult to make work with an aftermarket harness.
The one wire alternator has one wire that goes up to the battery side post of the starter solenoid. Do you have an XR7? And also, WELCOME!