1969 Barracuda Dome Light Question

Have you tried contacting M&H? They make perfect reproduction wiring harnesses for classic mopars. The M&H harnesses are sold by Year One.

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I see "rear lamp harness Barracuda Fastback" in their catalog. Not sure if it has the dome light harness you would need to contact them and ask.

Evans is another source. I bought AC and Trans harness from them years ago. Quality not as good as M&H but can make harnesses that are otherwise not available:

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M&H supplies directly to year one. They wont even talk to anybody on the outside, however if you can explain to them that the rear lamp body harness is missing a piece they can probably fix the issue, or being that it is a small 2 wire harness with dome light socket at one end and plug at the other, just find it used here, clean up the contacts, check the wires for cracked insulation and go with it.

The body rear lamp harness for my 67 notchback didnt come with a domelight harness at all, just the pink and yellow wires to the male plug. I am required to use my dome lamp harness over. Maybe M&H is assuming this as well simply because this smaller 2 wire harness is usually undamaged, and can be reused like a dome lamp harness in a coupe. Now his is completely missing, so he has to either find another one, or make up his own.