In the Bently service manual it says the following... "On all engines use a 5/8 inch spark plug socket with an extension or VW special tool no. 3122B to remove and install the spark plugs"
Here are the spark plug specifics
ABA (2.0 liter)
Electrode gap - 0.6 mm (0.024 in)
Tightening torque - 30 nm (22 ft-lb)
manufacurer's designation - Bosch (FR 8 DS)
Hope this helps...