roblightbody, I've checked: the high mounted 3rd brake light doesn't block my view, so that's good!
Thanks Ethel and Deeppockets, I'll have to check the colors of the speakers cables. But from what you are telling me, I would think this are the factory installed cables.
Deeppockets, in the boot, on the right side, I have found two connectors which aren't connected to anything: one has a black wire, so is ground and the other is blue and yellow, so, from the schematics, it looks like it is to connect the fog light on the right (my Mini is LHD, the the fog light is on the left).
At least I could use this ground plug, if I knew its reference.
There is also a ground point located at the right side of the boot: it's a bolt attached to the body of the car.
In one of the documentaion of the Mini, named "Schémas total MPI.pdf" (can't remember where I downloaded it, so I attached the relevant page), the electrical diagram shows "LAMP-BRAKE-HIGH MOUNTED (1076)" and it refers to the 3rd brake light.
I was hoping to find an unconnected connector in the boot, to plug my light, unfortunately it isn't present.
My Mini is from 1999, does the very last MPI had a wire for the 3rd brake light?
Anyway, I'll see how to cleanly plug my brake light.
For now, I have the wires arriving on the right side: I don't want to deal with the fuel tank on the left :-D
Deeppockets, I don't know how you managed to plug your light behind the fuel tank: did you remove it for another job, like changing the shock absorbers?
Edited by OlivierW2, 07 August 2022 - 10:01 AM.