I agree ... 12 volts is 12 volts.
Putting new halogen headlights in your truck is not going to create problems. Having 50-year-old wires and who knows how many unknown patches and disconnected wires hiding here and there ... that will create gremlins, for sure.
Putting halogens in my truck has been nothing but a blessing. But then, I did that after rewiring the whole truck.
