Wiring sub-harness: (civilian turn signals) turn signal extensions - rear: MG# 12750705 MG# 12750805
Buy a new duplicate of this original wiring harness
This sub-harness connects the rear turn signals to the primary turn signal sub-harness. Originally, the rear turn signals had sufficiently long pigtails which precluded the need for a separate sub-harness. If your rear turn signals still have those long pigtails, you are fortunate.