Rocker shafts only wear on the bottom. It's possible to turn them upside down, drill new oil holes, and plug the ones on top with brass dowels to correct the oil flow. Use a solid carbide drill bit, as the shafts are hardened all the way through.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!