Pretty sure he has the Hughes Banana Shafts that already have the groove's notched in them. I wouldn't doubt the eddy head oil passage problem one bit. Don't see how Hughes could have missed that on their super prepped heads though. Yeah right!
The problem I'm referring to with the rockershafts is inside the shafts. The drill used to punch the oil holes for each rocker arm can push a little flap of material that can block oil flow.
Everything you get from Hughes is top notch, just ask Dave. :finga: