The hollister set-up is mint. The Ford fan should come with a harness. If not Junkyard it. The kit can come with two sensors. On at 170 for low and 195 for high. I have the 195* for low (i got the wrong one) and a toggle switch for high.
100A alt is plenty if you don't have a huge stereo. Remember, it is only 100A draw for a second. Then it pulls around 35A.
The beauty part is that you can always get 40/60 relays from
www.delcity.com for cheap as spares..
The Hollister set-up is nice because the wires he uses are BEEFY!! Worth the money. yes, you could wire it up yourself, but when you see it, you realize why you paid..
HTH,
Dave