I know it is possible to install a switch to manually turn on the fans but I have no idea how to go about doing that. I know there are people on here who have done this. Would any of you be so kind as to share your knowledge please?

http://www.w-body.com/upgrades/manualfancontrol.html , that link should answer your question thoroughly. Also check out the forums there www.w-body.com/forum, and make use of the SEARCH function, chances are, what you wanna know has already been posted and answered a few times. If you have the center console w/ cig lighter right in front of where the console opens, I would suggest routing the manual cooling fan switch(s) to there and ditching the cig lighter if you do not smoke, makes for a hidden away switch panel. Just take a small piece of wood or other material and cut it to fit the cubby/hole left where the cig lighter and ash tray comes out of, that's what I did anyway. You can wire up the fans to always stay on, but that would leave you without the fun factor of playing with the switches...lol :D

Thanks so much, that explains exactly what I wanted to do. I'm going to do that tomorrow on my day off. THanks.