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I'm not certain of years/ vehicles, but chances are really good that if the trans case is round, it's an SAE bolt pattern. This is a standard that most equipment and anything built with a Cummins or many Allison transmissions use. I think the newer Ford diesels are now using this pattern, but I haven't measured one.
I know a guy that bolted a 4BT Cummins into a 1936 Farmall F-20. It's an amazing machine and spins our sawmill like a champ!
If you have a vehicle you're wanting to make a swap into, there was an adapter Ford made to mate their engines to a "Transmatic Drive" 6 speed auto starting in 1957. It's an early Allison transmission and uses the SAE pattern. I would say you may find this adapter for any of the engines Ford offered in these heavier trucks over the years to convert it to this pattern.