I purchased the GTA Trans Am tail lights. I can figure out the wiring but what about the two small lights? Cut em and tuck em is the only thing I can think of.

 

Two small lights aren't used any more. Cut them off the harness. Wire the additional lights into the harness in parallel, and you'll probably need a new heavy duty flasher for under the dash, or they'll flash like crazy fast.

 

You can get the taillight harness from a Trans Am or GTA , unplug behind the rear cover and plug the new harness in, no chop/cutting of the harness.

 

Except, there is no plug behind the cover.

Early GTAs, had a connector under the dash, then wires all the way to the lights.

Later models, like the 89 I stripped, had a plug under the rear seat.

 

just remove the small bulbs and tuck the wires up, replace the turn signal bulb socket from one from a trans am, and everything works perfect.

video showing my lights,
http://youtube.com/watch?v=yViyb41-Imo

EDIT: just noticed that you mentioned GTA and not a year, so maybe you have the older ones.

What I did when I had the older lights, is remove the bulbs from the small sockets, spliced in a medium sized socket I found from a car in the junkyard, drilled a small hole to accept the medium bulb and socket and used that to light up the outermost section of the lens (the part where I put the flasher) this way the entire panel was lit up when I had the parking lights on.
You still need to replace the stock turn signal socket as it is too deep for both the 85-90 and 91/92 GTA lights.

These images are before I added that medium bulb to the outermost lens area)

Parking lights


Left Turn signal

 

I have done this swap also.

If you got the 85-90 Trans Am/GTA style, and want all 3 section of tail light to light up, you will need a 3 wire socket. You will need to change the Turn Signal socket anyway, as the stock Formula one will not fit behind the tails.

As for the 2 small ones, I just clipped the sockets off, electrical taped the ends, and tucked them in the harness.

Hook 2 of the 3 wires from the new Turn Signal socket to the factory Formula turn signal wires, and splice the 3rd wire to one of the Brown wires in the stock harness, so the bulb will also light up with the tail lights, and still flash for the signal.

When I first did the swap, I only used a 2 wire socket for the turn signal, which worked fine, but I changed to the 3 wire for the lighting effect.

First Time with 2 wire socket with Tail Lights on:


After the 3 wire socket with Tail Lights on (The replective strip is just lit up from the Camera Flash):


Any questions feel free to PM or E-Mail me MNformula350@Hotmail.com

 

I did the 2-to-3-wire-plug swap too, to achieve my STS tail lights.