HUMMERLV, thanks for bringing that up.
David, skip the fans it you are looking for a MPG increase. I saw none what-so-ever. Furthermore, I really was unable to determine any HP increase. If my truck was for drag racing only I would still have them. But it is not, so I don't.
Here is a link to more pics and a clip of the near disaster.
http://elcova.com/groupee/forums?a=tpc&s=2826088551&f=2606011751&m=127107937
Again, I would recommend against them unless you drag race only.