I just orderd the Engineer's aux rad with the high CFM fan. MY question is after looking at the wiring dia. that came with the fan is: The Dia shows a fan relay with the system wired up directly to the 12volt post in the little red box by the fuse box on the driver's side fender bypassing the ign. switch. Why do I need the relay when it appears to me that all I have to do is run a hot line with a fuse from the post in the red box to an OFF/On switch and them back to the fan. One of the wires on the fan would go to ground. What do you think?