The story on the painted wheel-stud is this.....
For the
pr-89 cars, the heavier, keyed-locking nut is placed on the painted stud, and both of these were to line up with the valve stem...as delivered by Porsche. Helps you put things back together again "as delivered". If you still have the original-fitment tires and balance.
After 89.....it was just the opposite....painted stud pointed away from the locking nut.
It's all for naught anyway once you buy your first set of replacement tires and get them rebalanced.