Ihave a lifter tapping and am going to replace the lifter and push rodsand need to know the proper spacing for the lifter. Thanks for any help

 

You need to tell us what motor you have.
A v6 has push rods, a v8 does not.
V8s are overhead cam and have no push rods, only direct acting lifter assemblies.
Since both are hydraulic they do not work with any clearence.
The clearence is all taken up inside the lifter.
So a valve train noise due to a lifter is either a faulty lifter, worn camshaft lobe or push rod tip or some other associated wear depending on which engine.
Good luck.