Here's the result after I soaked it with Boeshield wax protectant to keep it from surface rusting: (Ignore the Jack Russell dog hair - that stuff gets everywhere!)
Before, when it was in the car. (I don't know what makes up the darker areas on either side of the stripes - but it is definitely some type of finish on there)
and freshly removed:
and after:
The solution did not affect the oil-based blue and yellow paint marks on the yoke and front u-joint:
You can even see the original welding seam where the rolled tubing was welded together. The black paint mark appears to be in line wth the two tack welded weights. Maybe it was a position marking for the balancing porcess?