This was actually after I manually leveled it, I know, I could get it better, but I might need to design a finer tramming tool.
The deviation was actually 1.2 before.
After using several models of printers, I have found that practically all beds are warped.
I have been able to come close to getting them flattened out by using tape at strategic locations on the bed below the plate.
Ahesive aluminum foil tape is about 0.1mm thick. Use it at the worst spots.
‘Invisible’ cellophane tape is about 0.05mm thick. Other types may give you more options.
I used a ruler and a Sharpie marker and marked a grid on my sub-bed at 50mm increments and used that as a guide for placing suitably sized pieces of tape.
Unfortunately, there is no way to reduce the high spot. You just have to build up the rest of the bed so it all is about level.