Still working on my 8.8 rear, was doing a trial fit with just one of the thick .265 shims on each side, because thats all that was in it when I took it apart, and wow it was tight. I tapped it in with a shim tool, but I had to pop the carrier out with my slide hammer. Well I took thick shim out of right side and put combo of 2 .100 and 5 .010 in which should be about .250 and slid in easy, also pulled out by hand. I could probably add another. 010 and might be tight enough, but my main concern is if I don't use the big shim, the bearing caps don't cover the thinner combo of shims, so if preload loosens up after a while shims could fall out of place. Even if just the two big shims will work, I have no way of adjusting backlash without taking one out. Unless there are different sizes of shims I can get. Probly need at least .200 thickness for bearing cap to hold it in.
Sorry for the long post, but my first rear end, want to get it right.

 

the shims are round and have a hole thru it that the inner race and shaft poke thru... Look close to see how much they can actually move after the bearing and shaft are installed... Sometimes you can reverse the order and put the thinner shims on the other side of the thick shim closer to the cap..... if your really worried about it, maybe a couple drops of super glue on the faces ?... real THIN.