This is the alignment info that comes from BMW's own system, and it doesn't differentiate between the Alpina and the Z8 so I am assuming they are meant to share the same basic settings. You can download a full PDF here.
Front:
Camber................... -0? 30'
Toe......................... 0? 04'
Track differential....... -1? 55'
Caster..................... 6? 44' (7? 44' with Dinan caster plates)
Setback................... 0? 00'
Rear
Camber................... -1? 30'
Toe......................... 0? 12'
Geom driving axis..... 0? 00'
Doing the kind of spirited back road driving I enjoy I have found the car in need of more negative camber at both ends, as my tires are always worn out on the edges before the insides. At this time there is only any adjustability in the rear, but hopefully we will have a front solution before too long. This shot shows the rear camber adjuster.