I must not be able to make myself clear. Chevys run one dedicated main galley to oil the mains through passages around the the cam bores and then to the mains. 2 other galleys oil the lifters and heads. Aftermarket blocks delete the bypass around the cam and feed the main directly.
I built an iron 3.58 crank based engine that had bearing issues and ended up breaking a rod when I tried to stretch it an extra couple of runs. A second similar engine had the same problem, but I continued to feed it parts and try various "fixes" to get oil to the rods - one in particular was a real problem. I tried everything every "expert", every Mopar book, every engine guy said was needed with zero improvement. After fighting this for 1 1/2 seasons, I pulled the engine and took it apart. We studied the oil system, looked at other engines, talked to a few guys who had done a few tricks they were willing to share and jumped into the oil system. We did some things that were common and recommended by some places, others things they said not to do, and somethings we came up with on our own. I went from pulling the pan and replace a bearing or two every 6 -7 runs to a full season of 150 1/4 mile runs runs at 72-7300RPM with a filter that stayed clean and rod bearings that could have been put back in the motor. I figured this out before there were these internet forums full of advice. That was 25 years ago and it was an expensive aggravating pain in the ***. So, I'm not making **** up, repeating what I read or heard or saw on a YouTube video, or guessing. I'm not going to debate whether what I've done is useful or makes sense. Or whether I actually have a clue, or not. I don't need to try to help. Just put a crossover tube in it and carry on.