What does bushing the lifters do for oiling? Does it "save" the oil for the mains/rods since it's not bleeding past the lifters or supplying oil to the hydraulic slack adjustment in the lifters? Do you still need to drill a small hole in them to give lubrication to lifter/bushing interface? Or is splash lubrication enough to not have the lifters seize in their bores since there's no load on them?
