Oil system is not working after rebuild by local builder. Guy gave up. Anyways by what the drawings say, after removing the oil pump, I should be able to see through to the other side of the engine, where the line continues to the oil tank. I cant see a passage way, or fish anything through, or even blow air through. What are the chances that this guy either blocked the primary oil path somehow. Perhaps using a later year gasket kit or something? Anyone who has torn down a 450 may have some knowlegde on this, please help.