Oil the rockers externally similar to Indy BB heads. Accessory holes line up with rocker shaft bolt hole. Re-drill and tap the accessory hole that lines up with rocker bolt hole to 1/4 pipe, but only as deep as original hole. Then drill rest of the way through, to the rocker bolt hole, aiming the drill bit, 1/16", at the rocker bolt hole until it breaks through. Then you make a custom rocker shaft bolt by drilling from the bottom up, deep enough to to be even with center of shaft, and another hole through the side of bolt even with center of shaft. Oil will go through the bolt into the shaft. Also use a grade 8 bolt. And if using cast iron heads I open the rocker bolt holes to 3/8x16. Can't do the 3/8x16 on eddys because of heli-coils. I also restrict oil by plugging and redrilling a .04 hole in the inlet fitting to each head. I do this even with LA heads on LA block.