if you have the under bonnet wiring all you have to do is run the wiring to the switch and tee off most wires on your headlightswitch using this
diagram and you need to find 2 more wires...the violet/red wire that should be in the dash loom wiring connector that the switch earths to make the circuit for the fog relay and a brown/white wire for the switch illumination that you tee off a brown/white wire in the dash loom.
If anyone is interested I have a couple of the plugs that plugged into the air con switch that will fit the foglamp switch left over from a couple of l3 dash conversions that I dont need I could cut it out with enough tail to piece into your dash loom and send it to you with a rough mudmap of what connections need to be done...