And as I have already posted at length, the holes in the shafts are in the WRONG location on W2/5 heads. They are off by a mile. You can groove all you want, but at a certain point (depends on spring load, cam lobe design, rpm etc) you MUST relocate the oil holes.
I have done roughly a dozen Gen II hemis and EVERY SINGLE ONE OF THEM HAD THE OIL HOLES CLOCKED WRONG. Every one of them had OE rockers and shafts.
And depending on the rocker, the oil hole is off on Pcar heads too. I just had to fix my personal shafts. They are drilled for hydraulic valve gear. So there is no oil hole in the correct location.