I'd hook up both hi and low beam to the one element. that way you won't be driving along at night and forget, click the hight beam switch, and say "ohhhh shiiiiiiiiiip".
I bought a LM Corvair a few years ago and drove it 300 miles home. It had a bad switch, and if you tried to hit the high beams the headlights would go out. deffinetly got my attention as I was on a winding country road, driving a bit too fast, when I discovered this. I don't recomend it.

Russ