Head gasket identification for the VW Diesel is easy
check (circled area) the notches on the gasket.

The 1.5 motor will have 2, 3, 4 or 5 notches.

The 1.6 mechanical motor will have 1, 2, or 3 notches.

The 1.6 hydraulic motor will have 1, 2 or 3 holes.