With the risk of getting crucified....I am attaching a picture of a Chevrolet C60L in this Ford thread.....but, I hope I can get away with it.
It clearly shows a white painted front diff cover. My thought was that during a service, the front and back diff covers might have been accidentally switched....but that theory won't fly on a Ford axle!! And to be honest I hadn't noticed the white painted front diff on the F15A picture I posted earlier.
Alex
picture source:
https://beeldbankwo2.nl/nl/