I bought my SPAL cooling fan and wiring kit from these guys:
Home | The-Fan-Man spal fan manufacturers, electric automotive cooling fans
You can buy the wiring kit/relay separately. Good prices and you can get the relay pre-wired with the proper wire sizes and fuse. I wired my cooling fan power source directly to the battery cable side of starter solenoid. So by-passed all the CR wiring harness for this and it works great.
You can buy 100 amp Ford alts from Summit, Jegs, etc. They work OK but you'll get something with cheap bearings (not US made bearings).
If you're spending the money for a new alt, I'd suggest you go to your local alt shop and have them make you a compact GM 1 wire alt clocked so it will mount on your Ford motor. I believe you can get these in 110 amp or maybe even 120. It never hurts to have extra output capacity! These alts put out quite a few more amps at 900 rpm than the old Ford alts do. That's when you'll need it because the cooling fan invariably comes on when you're sitting at the stop lights.