Am I missing something?
The entire gallery on each bank is oiled from one end. The tappets communicate oil flow through to the gallery on the other side, and to the next tappet.
Unless all the bushings are drilled on both sides, only the first tappet in each gallery will get any oil.

I've seen C932 (SAE 660) bronze recommended, is there a better choice?

Boffin Emeritus