I disagree though that Ford's systems were difficult for interchangeability. In fact,they were some of the easiest there was, because they were more "modular" than the rest.
Maybe, but they changed designs every 15 minutes. For example, they significantly changed the suspension and steering on my '63 T-Bird, so many parts won't interchange with a '62, and then they changed a bunch of stuff in '64 when they restyled the car. In '65, the 289 got a new timing chain style in mid-March of 1965. The engine in my Mustang was built March 10, 1965, with the old obsolete style. The newer style rubbed the timing cover. I was 20 years old when I tried to figure that whole thing out. They had 4 different 351s over the years (I count the 352 because it had the same bore and stroke). They had a 427, a 428, and a 429 all in production the same year. That's just off the top of my head.
Nothing against Ford, I like them and I own two classics and two daily drivers, but I've always felt that the left hand didn't know what the right hand was doing in the planning/engineering departments.
