Pinion depth will influence the depth of the pattern on the tooth (face to flank). Backlash will influence the pattern mostly from heel to toe. Some shops recommend .010-.012 backlash, some say .008-.010. No two gear sets are the same. I usually end up in the .010-.011 area. Changing the depth will require the lash to be changed as well - move shim from one side to the other in just about the same amount you changed the depth to get it close.

This is for new gears. Again, if you have used gears, you may have to base your settings on the coast side pattern. Used gear can be frustrating and you may never get them quiet.