Quite a while ago on the LED lights thread I mentioned in passing that I was considering converting the lights in the trunk lid to brake and tail lights rather than just the tail lights from the factory. Looking closer at the size of the housing, which is considerably smaller than the main housing, I began to wonder if perhaps the reason they were only tail lights was due to heat build-up considerations when the brake portion of the bulb would be lit. For that reason I decided that IF I did the conversion I would be sure to use an LED bulb in the housing to ensure I didn't melt the housing.
I had the trunk lid trim panel off to replace the license plate bulbs with LEDs and took a look at the tail light situation. The conversion to brake/tail lights is fairly simple and if you have all the equipment lined up should take you no more than an hour at most.
IMPORTANT NOTE: As I pointed out, the 7443 bulb with just the marker portion lit up can get hot enough to burn your fingers, so the brake portion probably puts out considerable heat. I would not recommend performing this modification with 'normal' incandescent bulbs as you may melt the light housing.
I use these LED 7443 bulbs from V-LEDs:
V-LEDS Part ID: 7443_20_R
7443 LED bulbs
Approximately 3 feet of 18-20 gauge wire
2 splice connectors
Female GM 150 metri-pack terminals (Stock #85335 @ PepBoys)
#1 flat screwdriver (to remove trim panel plugs)
Open trunk lid fully and remove trim panel.
Remove bulb assembly from housing.
Remove the OEM incandescent bulb.
Separate the bulb holder from the wire connector.
Crimp one of the terminals onto your wire.
Trim the flanges from the terminal that stick out 90 degrees (email me and I can take some before/after pics if you aren't sure what I mean) so that the terminal slides into empty hole on the wire connector.
Note the orientation of the terminals currently in the wire connector and slide your new connector into the empty hole until it locks into place.
Connect the wire connector back to the bulb holder, insert your LED bulb and install back into the housing.
Zip tie your wire along the current wire harness until you reach the third brake light wiring for the trunk spoiler.
Use a splice connector to tap into the 'hot' (blue) wire for the spoiler brake light.
Repeat this process for the other side.
Leave your trunk lid open and reach your foot into the cabin and depress the brake pedal.
With the trunk lid open, you will be able to see the lights.
If your brake lights do not light up, pull the bulb and reverse it. Most LED bulbs are polarity sensitive (they only work when inserted one way, unlike incandescent bulbs which will work no matter which way they are inserted).
Don't worry about 'frying' the LED bulb, as they are manufactured to prevent shorting if inserted 'backwards'.
Once you have everything buttoned up (trim panel), close the trunk lid and turn on your marker lights.
Now walk to the back of the car and compare the outer incandescent bulbs with the LED bulbs in the trunk lid. If you are using the V-LED units, you will notice that the light is brighter and more 'red'. Now have a buddy press the brake pedal and see how much brighter the LED brake lights are!
Now buy a second pair of LED 7443 lights for you main tail/brake light housing. :-)
I only had the one pair when I performed the 'conversion' so I made sure to install the LEDs in the trunk lid. The second pair is on order at this time, just waiting for them to show up.