79 Z28 Project Fast Times.........


Veteran Member
Oct 20, 2018
Naperville, IL
Thanks for the nudge. Work has been killing me this year so the car has seen very slow progress. With that said, I have made some progress. I was going to get the brakes finished up by installing the booster/master/balance of front lines, filling and bleeding the system before I started wiring. This lead to a brake pedal and bracket restoration. I was reading another thread that suggested if you have the opportunity to do the under dash wiring harness while the brake pedal bracket was out to do it as it would be a lot easier. So, I striped out the under dash and front to rear wiring harness to replace with the Painless Performance 20114 wiring harness I purchased.

If we remember back to post #3 (2 years ago) I started restoring the tail lights. Well, they are finished. I am very happy with how they came out. New lenses, gaskets, appliques to go with the repainted housings. These are not fully installed yet as this will be the topic of the next post thanks to painless performance #20114 harness.


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Veteran Member
Oct 20, 2018
Naperville, IL
So as I eluded to in the last post I purchased the Painless Performance 20114 Direct Fit Wiring system for 78-81 Camaro. I also purchased the power window and door lock wiring kit from them. So I started the wiring project and hit my first snag. After the old tail light harness was removed I was going to start at the rear and install from the rear forward with the new harness. The painless harness does not come with any wiring loom installed so I installed the split loom and went to loose fit it on the car to make sure I had all the light sockets coming out in the right location. Part of the test fit included installing the housings and checking the socket locations. Glad I did this. The turn signal and brake light sockets do not fit into the housings. The 3 tabs on the sockets are in the wrong position to fit into the housing. The reverse light sockets are fine. I then compared the sockets to the originals and it is obvious they are different. I called painless and they said those are the only sockets they have for this application. So now I am stuck either cleaning up the original sockets and then disassembling the sockets from the painless harness and installing the original sockets or buying new sockets with pigtails and cutting and splicing into the new harness. The attached diagram I did shows the difference. The angles are best estimates but pretty close.

The last picture is the reverse light sockets which are correct. I know it is hard to see in the picture. I have done a lot of research and the correct sockets are available. ACDelco LS7 sockets appear to be the correct ones.


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Feb 2, 2014
That stinks. I used my old tail lamp harness with a good cleaning. You’d prolly be okay as well with old sockets. A tail lamp harness could be ordered from American auto wire with right sockets? Stuff I got from them all fit exact, under dash and engine and headlights I got.


Veteran Member
Oct 20, 2018
Naperville, IL
Yeah, you hate to pay $850 ish dollars for a “Direct Fit” harness and then have to spend more money to make it work. 4 new quality sockets are about another $80-$100 with shipping and then my time to fix. I hope the remaining parts of the harness don’t have similar fit issues.


Veteran Member
Aug 4, 2012
Glen Ellyn, IL
Thanks for the update. You are an inspiration to those sitting on the sidelines.

25 years ago I had your energy and no time, now I have the time and no energy.

Strange how that works.


Veteran Member
Oct 20, 2018
Naperville, IL
So after a lot of research I purchased some rear turn signal and brake light sockets and they are the correct ones. I will swap them onto the 20114 Painless tail light harness and get moving forward.

For documentation purposes:

The correct rear turn signal and brake light sockets for the application are #12089348/12003759. ACDelco LS7. GM 8917962

The correct reverse light sockets are #12089347/12003758. ACDelco LS53. GM 8917822. These were correct on the 20114 harness I received.

The incorrect rear turn signal and brake light sockets that were on my 20114 harness as purchased appear to be 12089345/12003757. ACDelco LS6

as a side note, the quality of the sockets supplied on the Painless harness are probably functional at best. The locking tabs that prevent the sockets from coming off without pressing the tab are not dimensionally correct and don’t actually need to be depressed for the sockets to be removed from the housing. The ACDelco sockets I purchased snap into place when turned and will not turn off unless you depress the tab as designed.
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Bumblebee Builder
Gold Member
Sep 1, 2018
for a kit as expensive as painless, thats incredibly disappointing how sub par it is.


Veteran Member
Oct 20, 2018
Naperville, IL
I sent the technical guy at painless the above part numbers as documentation for their records. I’m still not sure if the harness I received was just built with the incorrect sockets or if their BOM specifies the wrong sockets.