We have both the 85 amp and the 125 amp in stock along with the wiring kits. The picture below is the 125 amp control setup for two 17" fans or you can run multiple smaller fans to get more radiator coverage. I have 4, 12" 1500 cfm fans on my truck to get 95% coverage and 6000 cfm.
The kit can be purchased with or without the wiring kit and comes with the temperature sensor and instruction for installation. The wiring kit includes all the correct wire, terminals, connectors, shrink tube, one or two 50 amp fuses depending on the kit and instructions on which wire goes where.
If you want information on PWM vs. Relays click on the link below.
http://www.thehollisterroadcompany.com/PWMControl.html