Yea, you have to move the diff. I did mine last spring. Common problem is the lower bolt seizing in the bushing, making it impossible to adjust. and the fact that they are so flimsy, they usually get bent
In my experience, It's impossible to really evaluate the diff bushings with the diff in place. Both sets of the bushings I replaced in my car were torn but was impossible to see that with the diff in place because you can't really see the tears unless you flex the bushing.
If you go to this page of my build thread, as you scroll down, you can see what I mean about the bushings tearing. also there is a pic of me about to put the diff back in where you can see where the two upper control arm bolts are.
http://www.zhpmafia.com/forums/showt...project/page24
Dinan CAI &Throttle body, ESS Tuning TS2, Bimmerbrakes gen3 headers, UUC SSK & DSSR. Achilles oil pump, VAC oil pan baffle
M3 Motor mounts, UUC Trans mounts, Modified clutch style LSD 3.15, TMS front subframe reinforcement, Koni Yellow sports,
H&R sport springs, UUC sway bars, BMW Perf. Rotors, UUC SS brake lines, Hawk HPS pads, CSL replica wheels,
Rotora strut bar, FXR HID conversion, M3 Mirror conversion, BSW stage 1 speakers