Ok on the liter thing
.
He said insert bearings in first post "Rebuilt my engine with modern main shells", then added the also part about cam bearings. If everything was cleaned after machining for inserts then there shouldn't be babbitt chips in the main oil supply tubes. The oil flow to the mains is gravity from the valve chamber so the chips would flow down to the mains not up from. The oil as far as I know flows in to the center section then to the back and then over the dam to the front and ether out the over flow tube or thru the hole in the front of the chamber of the A block. If that is correct oil path, then just cranking the engine over with the starter should not have moved the chips to the front section from the oil pump.
The B block had direct feed from the pump to the mains.