Here is the way I did it.
I took 12V from the pin on the FET which controls the fan, this goes to the main 12V line, so there is no problem drawing current from it.
I also installed a DPDT switch to select between normal and jet mode

the switch only pokes out a few mm from the case.
if you don't want the switch, just pull the red and brown wires from the connector and solder them to the 3rd pin on the fet (see picture), which is dead easy.
(hint for soldering to the pin; try 'tinning' the pin/pad first, heat it up with a soldering iron and add a bit of solder with the other hand. tin the wires too, then you can just touch the wire to the pin and melt the solder together.)

close up on the 12v point
This post has been edited by yaywoop: Sep 19 2008, 04:39 PM