V8Q accessory belt adjustment

[quk@isham-research.demon.co.uk (Phil Payne)]

Roger Galvin has battery problems that he's ascribing to poor accessory drive 
belt adjustment - he has about 1.5" of play in the thing.  He had the undertray 
off last night but can't see how to adjust it.
 
It looks like muggins is going to wind up on his back in a pub car park again 
tonight.  To save too much investigative work - can any V8Q owner (3.6 PT, if 
that makes any difference) tell me how this belt is adjusted?

-- 
 Phil Payne
 Committee Member, UK Audi [ur-]quattro Owners Club