DC CONTROLER

http://www.dccontrol.com/index.htm

it's a special fan controller thats supposed to work really well...here's the web site, search the different areas to find the products and descriptions of how it works

You can wire it to a switch, but you need some relays so you don't fry everything. A Bosch 75 amp relay seems to work well for most.

I personally don't see the point on running the fan constantly.. it pulls enough air that it really doesn't need to run every often anyway.. and when it does, it's not for very long. The DCC is just to eliminate headaches and to not ever have to worry about flipping a switch, forgetting to flip a switch, etc.

I've got an extra DCC unit at the moment I pulled out of my 5.0 before I sold it.. PM me with an offer if interested