Just to add to the confusion, has it been noted that the 53 GMC (in the link at two posts up) has a Hydra-Matic transmission (but this seems to now be missing); and, the oil filter
in this photo is from a 58-62 Chevrolet 261? Although, the variety of engine mods makes the identification difficult.
Are you able to find an engine ID pressed into the pad to the rear of where the distributor goes into the block? And/or post the
block casting code? 
