Instructions for converting 90-96 Beretta GT/GTZ/Indy/Z26 spoiler to use LED lights
Also available as a Word Document here 4.4mb

*LED stands for Light Emitting Diode. This device will emit an intense beam of light when electrical current is passed through it. LEDs burn cooler, require less current and last longer than conventional bulbs. They are also smaller and react to current faster, meaning they appear to illuminate faster than a conventional light bulb.

Special tools needed:

• Safety glasses - $5-$25 at local home improvement store
• Soldering iron - $5.99 at Radio Shack
• Hot glue gun (a little cheap one will work fine) - $1.78 at local home improvement store
• A rotary tool like the Dremel? Tool - $30-$100 depending on brand, quality and accessories
• A high-speed cutting bit for plastic that will work in your rotary tool - $3.78 at local home improvement store
• You may also need a screwdriver, Torx? driver, side cutters, needlenose pliers and a wire cutter/stripper

Parts needed for conversion:

• Third brake light assembly from your vehicle or a donor car. I used a GT/GTZ/Z26 style light from the spoiler
• Aftermarket universal LED* light bar or a third brake light from a newer car that uses LEDs instead of standard light bulbs.
• Hot glue, silicone or latex sealant.
• Solder
• Wire
• Crimp on connectors, electrical tape and heat shrink tubing

Procedure:

1.  Remove your TBL (third brake light) from your vehicle. You will need a Torx? type driver to get the screws out. On the GT/GTZ/Z26/Indy style spoilers be very careful when you pry the light out, the plastic of the spoiler will gouge very easily.
Disassemble the light and clean everything with dish soap and warm water.

2.  With your rotary tool begin cutting the red lens from the silver reflector piece. Cut along the edge where the two pieces meet and try to cut more in the silver plastic because it is softer than the red lens. WEAR YOUR SAFETY GLASSES. IF YOU DON’T, LITTLE PIECES OF MOLTEN PLASTIC WILL HIT YOUR EYES AND IT DOESN’T TICKLE. Your goal here is to separate the red lens from the silver reflector. Try to cut as straight as possible because these pieces will be glued back together later.
NOTE: Depending on the model and year of your vehicle you may be able to skip this step. I had to perform this procedure for my light because the two pieces were glued together. Other models and years may have third brake lights than can be more easily disassembled.
Figure 1 (Picture of High Speed Cutter Bit)
Figure 2 (Picture of Brake Light Seperated)

3.  Take apart the aftermarket LED light bar that you purchased. Remove the strip of LEDs and test fit it into your reflector piece from your TBL. The light bar I used had 50 LEDs so I had to trim off 5 to make it fit. To trim the LED bar, simply snip the circuit board with a side cutters. It should break cleanly. Be careful here, it won’t take much force and you don’t want to crack the circuit board.
Figure 3

4.  Before you shortened your LED bar, it was a complete circuit. Now that you’ve trimmed it you need to re-connect the last LED to complete that circuit again. LEDs use resistors to provide them with the correct amount of current and voltage to operate them. You’ll need to solder the open end of the resistor to the last terminal of the last LED on the circuit board. This will complete the circuit again and allow the last group of LEDs to operate at the correct amperage and voltage.
Figure 4 (Before Soldering)
Figure 5 (After Soldering)

5.  Now you’re ready to mount the LED bar into your third brake light. Once again, test fit the LED bar into your reflector piece and see if any part of the reflector piece hangs up on the edge of the LED bar. These areas can be trimmed with your rotary tool until the LED bar fits snugly into your reflector piece. On mine I had to trim the small ledges that separated the reflector bowls and I hade to take some material off the inner edges of the end two reflector bowls to accommodate the length of the LED bar. Once everything fits, run the wires from the LED bar through one of the bulb openings in your reflector piece. Now you can use hot glue to glue your LED bar into the reflector piece.
Figure 6

6.  This is the final assembly. You can use hot glue, silicone automotive sealant or latex tub and tile caulk. I used hot glue and it worked OK but something with more aggressive adhesion may be better. All you have to do is coat the edges of both the red lens and the reflector piece with your glue and put them together. You’ll probably want to clamp them to keep them from separating until the glue dries. After you’ve put the two pieces together you’ll need to make sure all cracks and openings are ABSOLUTELY WATER TIGHT. The spoiler on the GT/GTZ/Z26/Indy is not water tight and any leaks that penetrate your third brake light will ruin the electronics. You can now either seal up the old bulb holes or re-attach the bulb bar and seal everything up. Break off the bulb sockets from the old bulb bar so they don’t interfere with your new LED bar. I removed the conductive strips from the bulb bar to allow the new wires to pass through the end of the bulb bar where the connector used to snap into.
Figure 7 (Wires)
Figure 8 (Finished Product)