The long awaited video on how to use the Super Touch Plate in ChiliPeppr for perfect zeroing on XYZ axes.
https://www.youtube.com/attribution_link?a=ZK8YCBrLUaQ&u=%2Fwatch%3Fv%3Dselfqln0O4A%26feature%3Dshare
This is very nice. I added homing switches to my 3040 right away to get a good machine zero. With a bit more flexibility probing can be used for QA and for adjusting the x y Gcode to square like you did for the z height probe. It can also be used to scan objects. 
Can this Super Touch Plate be added to the grbl controller/workspace? I see it only when using the tinyG workspace. Thank you.
It would take somebody from the community to do it. Does grbl support x and y probing?