I doubt that those NHRA engines were as they came out of the factory. I'd bet they were altered a bunch. My observations are the
oil filter hanger drilled out to larger size hole and the
oil holes in the block would b drilled larger and the edge chamfered where misalignments occurred like where the hanger and block mounting surface using the gasket as a template. Anything you can do to flow more
oil to the bearings by reducing any restrictions I once was considering the two filter adapter in with the filters in parille. don't for get to replace the soft plugs with pipe plugs in the block galleries. If something happens you'll have regrets later if it turned out that you could have prevented that failure. 53 years ago I twisted a 406 to around 8400 RPMs, scorched a bearing and blew the side out of the block the next day