interior lamp question

[930lover]

Thanks in advance for your help. I am now working on fixing the little things on my 1986 930. The interior lamps will not light. I have seen photos of the wiring but now cannot locate them. The black (hot) wires are not hot. When I run a wire directly to the lamp they work. The problem seems to be getting power to them. From the passenger side (right-US) the black wire seems to run forward. How do I trace that wire and re-connect it to power? At least then the passenger side will work. The glove box light and front hood light work properly. I don't have a clock, I have a full size turbo boost gauge instead. If I can get the power to the light then I can work on getting the door switches (ground) to work, but for now, manually switching it is okay. Thanks again for having a great forum!