>>>*Noises can telegraph and sound just like tappets, but you say if you snug them up tighter they stay quiet?

*Curious if a valve job was done? If so, this can relocate the valve standing length. Then the rocker arm rides in a slightly different spot.

I might mention we have run these as close as .007" intake and .010" exhaust even with a stock cam and no harm.

If the noise is in the upper assembly it might be the rocker itself taking wear. I have seen some that after a valve job they were so far out of whack the adjuster screw was walking over to the edge if the valve tip.

That makes a "come and go" type racket that is hard to spot. Roll the cam up to where the rocker arm is free, slide the arm sideways and take a look at the wear pattern on the valve tip. If it reaches the edge, there's the noise....*EB