I recently purchased a bbc from a builder that came with a flexplate, I have a 4 speed that I plan on putting on it but i'm having issues finding the right flywheel. The block casting code is 14015445, 4 bolt main. From what I've been told and found on the block; it has a one piece rear main seal, it is externally balanced, and 168 tooth. Outside diameter is 14 inches, I measured the crank flange to be just a hair over 3.5 inches(hole center to hole center using a tape measure). The problem I'm having is the only flywheel that I've come close to matching is that it is a 91 and up flywheel (#14096987) not the 78 to 90, also all the other flywheels that come up when searching are two piece rear main seal.