I just bought a set of Ford Windstar fans off ebay and am now trying to decide which controller I want to use. Since its a dual fan setup, I'd like to take advantage of the versatility and get a controller that turns the fans on at different temps, say 170 and 190 degrees. I also want to put a switch in to totally turn them off if I want (I also want to attach the switch to a LED that is on only when the fans are off, is this even possible?) I've been looking around a bit and it looks like summit has a good selection of controllers. What are the different type of senders? I've seen "radiator probe" and some intake manifold plugs and the probes just look like silver poitny rods. How do they attach? Here are a few that caught my eye. If you have personal experience or any advice on what to get, post up. Index The ones I was looking at are p/n DER-16749, FLX-30331, and FLX-31165.