Quattro drive shaft question

[Mike Arman <armanmik@n-jcenter.com>]

Subject is a 1986 5KTQ - arrived here with the center drive shaft removed
and the U-joint removed from the two halves. Have a replacement U-joint,
have cleaned the CV joints on each end, checked the rubber boots, etc.

Questions:

1) The shorter of the two shafts has NO balance weight on it, and the
longer one has ONE balance weight on it. Are the two shafts balanced as an
assembly, or are the halves balanced individually, then assembled? I want
to put it together, and I want my chances of being right to be better than
50/50. Does it matter which way they are assembled?

2) Does the zerk fitting face the front of the car or the rear of the car?
(Or does it matter?)

3) I understand I'll need to align the drive shaft - it has to be straight,
both up and down and right to left - Bentley shows a straightedge tool to
do this, which I can duplicate if necessary - any other ideas? (Alignnment
is adjusted by moving the center bearing carrier side to side - slots - and
up and down, with washers). How critical is this, just do my best (which is
pretty good), or must this be accurate to within .000000000000001mm?

Best Regards,

Mike Arman