You can get the resistors for the turn signals from superbrightleds.com. I bought a couple when I replaced the stock tail lights on my '54 F100 with LED tail lights, but it turned out I didn't need them. I guess the flasher on my updated 12V wiring system compensated for the LED's. I think the resistors were around $8 each. Make sure you get the correct load resistors for you application. They can help you figure that out.