check pushrod lenght and lifters they could be too short creating clearance problems and that is the noise you are hearing.
That sux Brent. Have you tried a stethescope to see exactly where it (the noise) is coming from? The majority of my problems have been diagnosed using it as a tool with the metal endpiece removed. Speaking of "TOOLS" (brutusturbov6), (SLOcalgn) look whose back posting again in this section.
Scott Wile