Rocker shaft orientation?
DR
let the existing wear-pattern be your guide.
Post #6 edited
Oh dear; I am talking about the non-adjustable gear, with the stamped arms.
It has been a very long time since I looked at 273 rocker gear. However,the supply-hole orientation does not change. But perhaps the rocker arm oilers are in a different location for the enclosed wrap-around rockers. If those rockers redistribute the oil internally then the arm-oiler orientation would not matter.
Dr; sorry to confuse you.