OK, just done a similar hack to my 2004 3.2S. Hooked up a relay to the wiring behind the light switch so that if ignition is on fogs are on (LEDs). If low or high beam is on fogs are off unless the switch is pulled out in which case they're also on. The relay is off of eBay and accessible from above the driver side heater duct in case I need to pull it for purposes of appeasing Plod or at MOT time. If anyone wants a How To let me know. Daz