Jad, ok, NO drilling into the shaft. plug the top rocker hole (weld or setscrew). setscrew in the access hole in the adjuster side per your directions. drill .100" hole on valve side clocked just right to shoot a blast onto valve tip. All good so far? I have a bunch of shafts to choose from & some if not all (never noticed) have the banana grooves that would be on the bottom toward the valve side with the notches orientated correctly. (down/pass rear and down dr front). Good so far? is the OE oiling hole/banana groove enough for the adjuster/cup AND for the added .100" hole on the other side for the valve tip we wanna add? EDIT I reread your response again & I think I got it as in the OE shaft hole/banana groove DOES provide enough oil for the added valve side hole (or you woulda commented). Always a good day when you can answer your own questions!. Thanks again bro. this is gonna be a high RPM circle track 360 & I dont wanna leave anything on the table nor the embarrassment of a DNF!