Need help with SuperCam step size settings

The x axis, actual travel, on my Taig mill is .001 per inch longer
than it should be. I assume the problem is related to a less than
perfect 20 tpi leadscrew. I calculate that I need to use 7992 half
steps instead of 8000 to compensate for the error. If my math is
correct that will translate to .000125125 instead of .000125 travel
per half step. So far as I can tell the SuperCam 'set step' commands
allow for a 6 digit field. Entering .000124 or .000126 would clearly
make the problem worse. I haven't been able to find a way to change
the number of half steps to 7992. Is there a way to make this
change? If not is there any other way to compensate for the error?