Dr. Diff is a great resource for rearend parts. Rock Auto has burned me too many times. mad

The OE wheel bearings seldom wear out unless they have been exposed to moisture or not lubed.

As far as adjustment, I always have done it by feel. If you've done it a few times you know when it "feels right". Sorry, can't help with exact end play numbers.

'63 Dodge 330
11.19 @ 121 mph
Pump gas, n/a, through the mufflers on street tires with 3.54's. 3,600 lbs.
10.01 @ 133mph with a 250 shot of nitrous an a splash of race gas. 1.36 60 ft. 3,700 lbs.