Sam,
That's a great question and one, on which, I would have to differ to Jonathan. In my research so far I have not discovered any GG-1's that were painted black but, as we know, the green color used by the Pennsy would sometimes be "interpreted" as black because they were so dark. I would imagine a very shiny dark green would look black to some. I have discovered along the way that as the G's passed from one railroad to the next, there were occasionally "one of's" and so it is possible a black one had stripes added by folks who adored the G's. It is also possible that a GG-1 was restored in a very dark green or black and that I am unaware of.
