My take on the oiling system crossover tube for the small block

In stock configuration, the left galley supplies the lifters, period. Not the rocker gear, not a main bearing. The oil for that galley comes from the main saddle under the #1 main. #1 cam bearing also is fed from there. If you don't need to pressurize the lifters, why create a roundabout circuit, feed and pressurize the oil in a galley and feed #1 from the end of all of that, instead of just fixing the issues with right galley, keeping it full and feeding #1 as designed. Block the left galley at the source (#1 main) and keep it dry. Keep it simple and direct.

Once the supply to the crank is squared away and optimized, the second part of the equation is controlling and keeping the oil on the crank, instead of squirting off to the cam bearings and the heads. Yes that stuff needs to be lubed, but you don't need to pump the pan dry to do it.