The three wire SI alternator is definitely the one to use, built in regulator that is easy to test and replace and simplifies the wiring. I have my sensing at the dash where my junction block is. I fed the junction block with a #8 wire then ran another # 8 to a second junction block at the rad support. You may as well go with the ford style starter relay while your at it as that is also a good place to connect accessories, the cable to the starter is only live when starting and keeps the start wire from the ignition switch away from heat, great for connecting a remote starter switch to as well. I found the junction block on the rad support great for hooking up the fans, head lights, horn and using to power a timing light, kept all the wires on the number one spark plug side of the car.
