How do I determine net lash pushrod lenght
 

I have a 98 with a W vin engine that uses a net lash adjustment on the rocker arms.

After replacing the lifters, rockers, nuts and pushrods with new parts I still have some play in some rockers.

I know I can get pushrods in longer lengths. In .05 increments I believe.

On adjustable rockers you normally tighten the rockers 3/4 turn past zero lash. I assume that a net lash system should have similar preload.

Does anyone know how much preload you should have on this engine for stock lifters?

I'm trying to determine what length pushrod to get without taking the intake off to measure it.