headlight killer

I need to replace the driver's side for the third time (I have never had to replace the passenger side.) The wiring for the lights doesn't look as if it has been hacked and I replaced all the rubber isolators when I flipped the lights for the winch install.

I am leaning heavily towards switching to H4's, and using the passsenger side wiring to trigger a relay that would provide power to the lights. any thoughts or suggestions?

Where do you get the lights? Odd, since, you don't do that much driving anyway do you?
I have only had to replaced one sealed beam since I got the deuce in 1995.

Try idling the engine up a little. The vibration at idle has been known to make headlights die young.

used lights (traded other used "stuff" for them). I probably have only driven the truck 1000-1200 miles in the 18 months or so that I have had it.