Mitutoyo plunger dial indicator holder dovetail back

Added a M7.5x0.5 thread to the bottom of my dovetail holder
https://www.thingiverse.com/thing:3603753
The design screws into the extruder nozzle thread on a cetus and is rigid enough to make 0.001 mm Z axis measurements (step and micro stepping position errors).

This odd thread is on the top of my digital 543 series Mitutoyo dial gauge. Normally a hollow cap covers the opposite end of the plunger protecting it during measurements. This design has sufficient plunger space for 1/2" travel gau