kh15- That's correct but don't dremel too much or it gets sloppy and the diff will move around in the case. I have dremel bit about the same size as the bearing curvature, just a light touch which appears to just "scuff" the case is usually all it takes. However, the most important thing is using shims correctly to get proper backlash on the ring-pinion gears. Getting proper mesh would help more so than proper treatment of bearing with bad backlash, so get that right first. The way they tell you to shim in the manual isn't "always" the best for each car, so play with that for a bit.
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