I got brighter lights by installing relays to power the lights. The original wire from the High/low switch turns the relays off/on and a heavy gauge wire from the main power buss supplies the power to the lights through the relays. Juice for the lights has to travel from the power up source through the firewall, to the headlight switch, to the High/low switch, back out the firewall junction block to the splitter and on to the headlight. Every solder, junction and switch can add a bit of resistance and cause a voltage drop. I was getting less than 10 volts at the lights, I now get 14+. The lights are vastly brighter with standard lamps. Good ground is needed as well.