Here is my latest probe run after thoroughly cleaning the glue off of the plate and doing 2 probes per point with bed at 70c and hot end at 180. I also increased the trigger threshold to 600 so it hits slightly harder. And it now has a stiffer Piezo upper mount I printed in Taulman 910. My BuildTak magnet system will be here tomorrow. I ordered an extra steel plate so I can have a Buildtak and a PEI option. At this point I won't be attempting to make the plate any flatter than it is.
edit:
I did a calibration print for square, and it appears I'm good other than a fraction of a degree off 90 degrees Z to Y. So my Z uprights are not quite vertical.
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