I would never do it because it's silly but if I were to, I would add a 2nd switch to a relay that supplied power to both the hi and low beam wires at the housing. It would be important to diode-isolate the circuit and the wires from each other so the system still works normally when used on the road (with the factory switch. All you'd need is a couple of diodes, a 30A SPDT relay, a switch, a fuse and a black belt in the 12V arts.
You kids today and your crazy ideas.

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2006 CRD
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