Here’s the whole thread: Adjustable heat bed - glass mount
In inches the difference was 0.007 from edge to center. But that’s with the added weight of the gauge.
I’ve scrapped that mount in favor of a different style. There’s no way my mount will work with a different dial indicator.
I went with something more similar to this one: http://www.thingiverse.com/thing:551366
I just retro-fitted that design to fit my gauge.