Just so you know too, "nose down" does not mean pointing down at the ground. It means nose down in relation to the drive shaft angle. So it could actually be point UP when you're done....
That's a good point, when I did mine I used the factory angle and after I got it in the car it was sort of pointing up. I thought for sure I screwed it up., but it works like a charm.
I guess a better term would be negative pinion angle.