Instead of tubing the block theres an article somewhere about tying the two main galleries together right about where the rocker oiling intersect the main gallery. Sorry I dont have all the info at this time.
That was some old stuff trying to get oil to that galley directly instead of taking it off the front main. May be relevant with hydraulics. Solids? No oil in the passage needed.
There is validity in putting oil into both ends of the main galley. Especially at higher RPMS. Takes some more effort though and is usual done along with other mods.
