340 T/A Demon??

Back in the day things were not as automated on the line as we know of today such as parts being ready when needed. They probably had some guy pushing carts around with rear ends on one and trannys on another and engines on another and so on. Now things are a lot more likely to be at an arms reach and available when needed due to this automation, but back in the day there of course was an assembly line that was moving along and i would say at several times one of the racks became empty that had the needed part for that particular unit BUT the line had to keep moving and as there was another rack that had a motor on it that would work and progress could continue with installing that motor, that's what took place. The super made it very clear that production was the key to his bonus and you damn sure better not be the one that caused him to not get it either. It might be that some cars that called for a 7.25 rear got an 8.75 because the rack was empty that held the smaller one but would get em out of a bind. Just a thought.
Small Block