Back Spacing, which way?

Nice job of explaining it Blu, and a good illustration.

The only thing I would add for clarification to what Blu said is that when he is describing the offset (+6, +3, +16), that number is in millimeters. For some reason backspacing is typically called out in inches and offset is called out in millimeters. Don't know why, but wanted to clarify because it confused me for a minute too.