Ok so backlash shims on this car from my reading are the c-clips cut to a different thickness (and they are a different thickness on each side of the diff, done so that the ring -gear is shifted closer or further away from the pinion gear).
And the bearings are held in place by the same c-clips. Removing the axle shafts is generally pretty easy, requires a slide hammer. The difficult part is the bearing races. They can be pulled with a bearing puller jaw, but they are pressed very close to the diff and require a bit of massaging to get them spaced out enough so a jaw can grip them. I have access to a press if I need it.
Install should begin Saturday assuming my dial indicator and magnetic stand comes in on time; its still not here, but everything else is.
I bought my diff from Harold at HP Autowerks and my M3-spec LCAs from ECS!
'08 E90 w/ just boltons
'09 Z4 sDrive35i w/ just boltons