I switched my front incancescent bulbs in the parking/turn light to bi-coloured (white/amber) LEDs behind a white beehive lens, and the rear bulb to red LEDs behind the red beehive (I tried a white LED, but as commented above the light was bright pink rather than red). I also added a second brake/turn light LED in the reflectors above the tail lights for additional visibility. It all works well. Rather than tampering with parallell resistors I swithed the flasher relay to an electronic. It was very simple, just plug and play.