Thanks, I'll be using your method. I have an LED strip attached to the top beam of the car, so connecting the wires for the tail lights to it should be simple. I'll be using rounded 3mm warm white LEDs for this. I'll drill into the modified plastic lenses as far as I'm comfortable doing, and then CA glue the LEDs in.
I tried using the spare LEDs from strips, connected to the strip as per @stan2004, but I was never able to successfully solder them to the strip. My strip did not look like Stans though.
On a related issue, the drumhead (I believe that's what it's called) was lighted with a tiny little incandescent light. While I was messing around with the lights, and they had been on for a while, I accidentally touched the bulb. It was incredibly, incredibly hot, so much so that the plastic holder for it was starting to soften. I'm guessing that after a while, the heat from it would have discolored the plastic drumhead symbol. I wasn't planning on modifying that light, but I replaced it with a nice 3mm LED.
BTW, these cars are new, and I've only had them on a test track to check out the lights.
