Hi Paul

A assume you are referring to the rocker arm adjustment ?

The method is to rotate then engine until the injector rocker is on the highest point of cam i.e injector fully down.( use a Dial gauge) Then turn adjuster screw clockwise until increased resistance is felt (quite obvious when you do it) then back of the screw the correct preset amount.

If you ring Auto data they will give you the exact setting for your engine code most likely 180 or 220 degrees

Aidan