12 Bolt Bearing Kit - Need Help!

[72Thunder]

Hey all,
I recently found out that my differential carrier in my 1972 C10 had succumbed to 42 years worth of wear and tear (and maybe even a few burnouts). It is a non-posi with presumably a 3.07 gear ratio. I had went onto Summit Racing and ordered my self an Auburn carrier and Richmond 4.10 gears. However, I decided to shop at my local Bumper to Bumper for a master bearing kit and they came back to me with 4 different kits to choose from that all varied in bearing size. I am wondering if anybody has any information about these and the part numbers on bearings and their whereabouts without tearing out all the guts!
Thanks in advance!