Many use a "squirter" hole in the side of the rocker body - aimed in the general direction of the pushrod and in many cases the spring as well. Harland Sharp do not squirt oil at the spring but they do squirt at the pushrod tip. If you're oiling through the pushrod then there's no need at all for any additional holes in the rockers or adjusters. Keep in mind that every place you allow oil to flow equals a reduction in oil pressure.