I used two 15 inch fans from advance auto. I didn't do a thermostatic switch, I ran two seperate switches into the console so that I could turn them on and off at my discretion. And during the summer, I ran no thermostat. THat fixed all of my overheating problems with summer traffic here in atlanta. Of course, some will say thats oh so bad but I say I did it and it worked wonders for me!