66' 273 Knocking/Ticking

Also, regarding lateral movement; if the rockers and shaft were grooved from wear you may never get them to be quiet. Even if you re-assemble the rocker arms on the shaft in the same order, you'll never get them in the exact same place. They'll jump sideways and tick. Even hydraulic cams suffer from this. Unless the rockers are really badly worn, just replace the shafts and you'll be fine.

Obviously try an adjustment first.