You're right. I think there's a couple of guys. One was EmperorFives but he hasn't been around for a couple of years. The other guy, I can't remember his name.
Awesome! Have you ever found or heard of a note (if it's even possible?) on which only 1 number was inverted?
I don't think that's possible because the numbers are side by side. Each individual number is on a wheel which is set by rotating it at the start of printing.