LA small block,Do you put an oil passage in your head stud?

There is zero reason to machine the stud like that. As Pittsburghracer pointed out a .040 hole will flow a ton of oil. If you have a roller cam (solid roller...I haven’t used a hydraulic roller is so long I can’t remember how they are done) the 2 and 5 cam bearings are grooved so you get full time oiling to the heads anyway.

And the leaks at the rockers determines how much oil moves up there anyway.

If you have a SFT and studs and you think rocker oiling will be an issue just put a groove in the 2 and 5 cam bearings. That isn’t needed either but it’s better than machining a stress riser in the stud to fix an issue that isn’t there.