When i upgraded the lights on my 200B I did the inner first and ran a relay because they were 135watt each and put in new wiring. When i did the outer lights, i originaly ran 60/55s but that was pitiful. I then put 100/90's in, and well, they weren't any brighter. Found a 2.5V drop across the wiring.
Rewired the entire light circuit, including the wires from the switch to the engine bay. Used something like 4 relays, and its abit messy, due to the fact the highbeam relay needs a relay to switch it...go figure
but its covered by a metal cover and theres split loom throughtout the vehicle.
There is now 12gauge wire everywhere for the lights...and damn its bright. I had to put the inner lights on a switch due to 470 something watts of light alone not being very friendly to a 50amp alternator.
Thought about Datsunboy's idea of wiring them to the ignition switch...But had had enough with the relay problems and decided i was happy with working lights
So in conclusion. Rewire the entire thing. If your handy with electrics, do it yourself. You'll save a bundle and you'll be able to say, hey look, i did that! Just do it abit at a time and you shouldn't muff anything up. If you don't like electrics, get a sparky to do it. This'll say problems further down with light switchs triggering indicators and wiper switchs doing the headlights