Add a secondary circuit with a switch to turn them on, an indicator light would be good too.
If it was me I would us a DPDT Sw.
One half of the sw (three poles in-line) will be for a std Aux Light Circuit, so lets say when the sw is up the Fog are on.
The other half (the other three poles) can be used to turn on/off the power to the other circuit, (you would need to determine the power wires going to the OEM Fog Light Sw) which will allow the Fogs to work with the headlights if the switch is down.
Up or Down that is the question...
OR… and I am not sure if this will work, maybe Bob or the Buggman can help, find the power wire going to the OEM FOG Light Sw and run it either directly to the battery or put it on a Ignition “On” lead; that way there will be power there all the time or with the ignition is on and you can control them from the OEM Sw.
4x4, 5sp, Std Cab, Stepside, E4 Red
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