Ring and Pinion Question

take a fine file and file across the edge of ring gear, if it digs in , it's a pro gear, means it's soft. street gear the file will sail across it , not dig in. do not use a grinder!!!
I was trying to search the part number on the gears and had no luck. I just noticed this morning that the numbers 9310 are stamped on the ring gear in another location, but thanks for the tip.