273 rocker arm adjustment

x2 on the banana groves and oil also cools do not restrict use a hv pump
typical shaft wear
steel can wear well with iron- up to a point of spring pressure and lube
hard chrome and iron wear better but do not use flash chrome and I do not much like induction hardened (surface hardened not deep case hardened)
hard chrome and bronze wear even better
get to high spring pressure it's a whole new ball game
chrome moly heat treated shafts and all that