Yep thats wot I did.......... Nice n easy. To pass an MOT ur car only has to have one reversing light so best way I found was, buy a red bulb and replace the normal reversing one on the drivers side. Disconnect the wires to that bulb which are part of the reversing lights.
Now wire from the bulb to the front of the car (only needs one wire, the earth is already there). You can easily use the cable trays under the sill of the drivers door. (just pulls up). Now connect a wire to an illumination wire in your dash. If you dont want to pi## around its easiest to take one off of say the hazzard or heated window illumination (one which has power only when the headlights are on).
Now connect up the wire from bulb to the wire from the illumination switch with a normal flick switch in between. Job done.
this means the switch will operate the fog lamp but only when the headlights are on.
I mounted my switch for it in the coin holder, but thats ur own choice.
Takes about 30 mins max and looks totally cool and professional if you hide that wiring properly. NICE, MOT PASS........... ;-)
