How tight do you get rocker arms when first putting them on a chev 350?

start w/number cylinder turn engine over till cam lobe at max lift then rotate engine til cam lobe goes down then run rocker nut down while turning pushrod by hand til it has a little drag while turning pushrod then stop this is zero lash then do the next vavle same way tl you do all of them

There is an Excellent description of this procedure in any Motor's or Chilton's manual.