v6 maintenance

[David Erickson <davide@Rational.COM>]

Perhaps this subject has come up before.  If so, can someone
email me a response instead of cluttering up the mail list
with replies.

What is the recommended mileage for V6 timing belt replacement?  

What is involved?  Is it a matter of setting the #1 cyl. to tdc
and aligning punch marks on the camshaft gears with the top of
the heads, and aligning punch marks between the crankshaft pulley
and the intermediate shaft, just like a 5 cyl engine but with an
extra head?  Is the belt tension set the same way?

Are there two belts, one per head, or does one belt serve
both heads?  Is the belt internal or external?

If a V6 timing belt breaks, is there a high probability of
consequent head damage, or is there sufficient clearance to
prevent piston/valve collision?

Boy, not having a shop manual really sucks.  And not getting
a response from Bentley is worse, especially after having shelled out 
the mandatory $100+ for manuals for the last two Audis.  I called and 
asked what their plans were, they promised to get back to me, but that 
was two weeks ago.

-Dave Erickson