So this is where I am at 1 year later and getting good prints but having leveling issues all the time. I can level my HBP with a glass bed at the 3 points and using a dial gauge be at .00 mm at each. I move to the center, left center and right center ,and get -.06 (ish) every time. So it seems that the y-axis rods sag ever so slightly in the middle causing the plate and nozzle to be too close. I have fiddled with it and got it to work but with a modified z-axis and accepting I can only print at .2 layer height unless I change settings. But the goal would be not to compromise. DO you think just removing the left extruder setup would fix the sag? Is this the best solution? Thanks.