D850 Auto Fine Tune ?

Hi, does anyone know how to do the Auto Fine Tune on the D850 and translate the numbers to the values in the tamron tapin console.

I see 3 ranges on my 150-600mm G2 lens, 7,2 ft, 20 and infinity, do I need to do the auto fine tune using that distance and do I need to move manually the dial on the lens to each of those distance and then put my camera at those distance ?

Do I still need to follow the 12 fine tunes remove highest and lowest number average it and that is the number i put on each of the distance ? How about if I get some that are -6 and then get a +6 how do I average that out?

I know I must be complicating this thing.

Thank you for any help...