I use to use a set up from Flex-lite called the "blackjack". It comes with all of the hardware and sensors. I had it in my 83 toy with a/c. When it worked, it worked great. It pulled plenty of air. The design is flawed a bit. They put the circuit board down in the middle of the main part of the heat being drawn from the radiator. It failed on me 4 times and finally got my money back. If they had relocated the board where it wouldn't over heat it would be great. I don't understand why they wont re-design it. I'd love to have an electric fan back again. I installed the mechanical fan back in for now. I did run across another build thread that the guy is using a 16" slimline puller. It has the sensor and board located anywhere you want. He got it from summit racing. I am still using r-12. It's a few degrees colder and more expensive but I think it's worth it.
I'm going to keep the stock mechanical fan. My idea is to add an electric fan in front of the condenser and behind the grill in order to push air through the condenser while I'm at low speeds around town/in traffic. So I'll have an electric fan to cool the AC and the mechanical to cool the engine.