LED 3rd brake light conversion how-to
 

I posted this on Rennlist, but thought someone might find it useful here. I converted a "baskethandle" 1995 third light to LEDs. This should also apply to the later style.
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I got a few emails asking for details about how I replaced the bulbs in my '95's third brakelight with LEDs. Hopefully this information will be helpful for some.

There are 24 bulbs in the housing. I bought 6000mcd 5mm "ultrabright" red LEDs from www.allelectronics.com. Based on the LED specs, I elected to use four sets of 6 LEDs. Each set of 6 is wired in serial, and has its own 50-ohm resistor. Quarter-watt resistors would be OK, but I used 1/2 watts. Each of the 4 sets of 6 LEDs is then wired in parallel to the original power and ground wires. I found some crimp-style female bullet connectors at mcmaster.com that allowed me to plug into the original power and ground without cutting anything, and keep everything reversible.

You can use the original circuit board, but I made a new one, so that I can easily revert back to stock if necessary. I bought a copper-clad board from the same place (all electronics) and used my drill press to cut the little indentations and LED lead holes. I soldered the LEDs to the board, mounted it in the enclosure, and installed it in the car.

It's about the same brightness with the LEDs as it was with the bulbs. It also has the nice instant on/off characteristic of LEDs, and they should last the lifetime of the car. Total cost was about $40.

This is the original incandescent board with the burnt-out bulb:
http://www.omsoft.com/cokeefe/pict0019_jpgprep.jpg


The new board with LEDs:
http://www.omsoft.com/cokeefe/pict0079_jpgprep.jpg


LED board in the background, stock board foreground:
http://www.omsoft.com/cokeefe/pict0081_jpgprep.jpg


Old and new boards side-by-side:
http://www.omsoft.com/cokeefe/pict0082_jpgprep.jpg


Testing the LED board:
http://www.omsoft.com/cokeefe/pict0101_jpgprep.jpg

You can see the resistors here (under white shrinkwrap). I mounted them inline with the wiring, not soldered to the board:
http://www.omsoft.com/cokeefe/pict0107_jpgprep.jpg