Flat Back for Cheap Metric Dial Indicator

Flat back to replace the back with a lug that ships with the cheapest metric dial indicators money can buy on eBay (~$9 delivered!).

Details: I really wanted to use kyoday's awesome [Gauge Dial Calibration for creality Ender 3 MOD](https://www.thingiverse.com/thing:3029416), but the rear lug on my dial indicator got in the way, so quickly threw together this flat back.

The provided settings are just what I ran and worked great in PLA, printed with the counter-bores face down. I didn't bother with supports for the counter-bores, figuring it's easy enough to spin a small drill bit or chisel out any offending overhangs if needed. You can probably go lower on the infill since it's not structural.

You can easily kill the counter-bores altogether in the code, but you may not be able to use the screws the indicator came with.

Inside the dial indicator there's a retaining screw for the main spring around the outer perimeter, it was loose so I tightened it down slightly so the bac