[VetteVet]

Hi Jemo.
If I understand you what you have is just the Mini column and the wires that run through it. Everything else is GM. If that's the case all you need to do is to find out what wires in the mini column do what and then matching them to the GM harness should be easy.
I know the GM wires by heart but I don't have any experience with the mini wires.
Does the mini cooper have the integrated brake and tail lights or are they separate with bulbs for each? Is the horn button part of the column?
What's the color code for the Mini column?

Here's your wires for the GM column.

1 Black for the horn
2. Light blue- left turn signal on front.
3.Dark blue- right front turn
4.Brown- power wire for the hazard lights
5. Purple- power wire for the turn signals.
6.Yellow -Left turn/Brake in the rear
7.Dark green-Right turn/brake in the rear.

That's the best I can do at this point.