I am working on a tube chassis rock crawler with a 2002 GM 6.0, 4L80E, Atlas 5:1 and Unimog axles. When I go in to edit the tire size and gear ratio, I get an error trying to go over 7:1 gear ratio and over 40" tires. The tires, aired down, measure 41" and the final ratio in the mogs is 7.56. I know it's not a big difference, but I would like for everything to be as close to correct as possible. Is this simply a system limitation or am I doing something wrong?