I used a GM alternator that is rated at 100 amps as the bosch was too big to fit without modifiying the deck lid.  I suspect this was a result of installing the AC in the configuration I did.  The GM alternator is quite compact.  Surprisingly, the alternator fit with a few washers to space it properly.  The Bosch pulley was a direct replacement for the GM unit.  My only complaint is that it gets quite hot (typical of these units) which begs the question of longevity.  The Alt light stayed on using this alternator until a switched 12 volt lead was added to the GM wire equivalent to the VW alternator warning light.
    

  Belts I ended up with after some experimentation:

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