273 rocker arm adjustment

IMHO, if you offset the oil hole in the rocker shaft from the oil hole in the rocker slightly when the rocker is at rest (lifter on base circle), so that there are just a spurt, or spurts, of oil per valve lift cycle, then I'd stick with the .100" hole or so. You don't need a ton of oil there but the timed spurts ought to give some oil control.