Great posting for the four separate tail lights ....
For those of you guys with the rectangle tail lights and want an LED replacement, Technostlagia tells me "We are working on a complete LED taillight for the Cobra. It won't be ready until this Fall (2008), however. Our light will be higher quality and lower price than the incandescent light that you can buy today".
Someone on CC used their '42-'46 ford kit as a replacement to illuminate top and bottom of the rectangle.
http://www.cool-leds.com/
I'm currently using the 25 LED 1.5" x 1/5" 1157 replacement, but want a bigger, full tail light. Will wait to see what their system looks like ...