So, this just arrived 🎉. I’m feeling excited about getting nerdy with leather thickness

That worked 👍. Here is similar guidance from Mitutoyo.

There are two ways the zero the gauge:

1. If the dial hand is not too far away from zero, you can simply adjust (turn) the bezel to read zero.

2. If the dial hand is too far away from zero, slightly loosen the screw found on the side of the frame that holds the dial indicator in place and adjust the indicator up or down until the hand is close to zero with the anvils touching. Then turn the bezel to fine adjust the zero setting.

Thanks for the heads up. I'll have to have a look to see if my older model has the screw on the side of the frame. I wasn't aware of this.

So, mine doesn't have it. Must be internal, or perhaps older models don't have that feature.