How to open up rocker arm oil passages.

Hello all.

As part of my reassembling of the cylinder head after shaving off .075", I soaked the rocker arms in the 'new-improved' EPA compliant carb cleaner and blew them all out with compressed air. I also gave them all the once over with a toothbrush.

Upon adjusting the valves with the engine running, I noticed oil is leaking out at the rocker shaft between the rocker arms and spacers, but some rocker arms have oil flowing through the V groove valley in the top of the rocker and some don't.

What is a reliable way to open these rocker arm oil passages up?
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