The plug on the sump plate is the low point in the engine. Ater removing that you could only get out more oil by removing the sump plate and timing covers and hand wiping all the surfaces. However, that would be completely unneccesary unless you had a major entry of dirt, grit or loose sludge into the oil and you were determined to assure that all surfaces and oilways were clear of such dirt, grit or sludge. In that case, a complete tear down would be called for because you would need to clear the crankshaft and other internal oilways as well.
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Richard L.