So I have the 6 red bulb Trans Am grid tail lights. I replaced all the bulbs, including back up bulbs about a month ago. The last red bulb on the passenger side is noticeably brighter than the rest. Something I had noticed when changing the bulbs is that two of the sockets on the passenger side had been replaced by a previous owner. If I recall correctly, the two inside sockets are 3 wire, and the outside bulb is only two. The socket on that outside bulb was a 3 wire, but only had two wires connected. Can anybody tell me what wire does what? Thanks.

 

The last bulb should be a parking light only, and by looking at a spare taillight wiring harness I have (it came off an 88 f'bird, I believe), the RHS parking light wires are dark green and black. The brake/parking light wires are lt. blue, brown and black. Make sure you're using the right bulb.

Hope this helps.