I have used all of those cases without a problem. Even the 741, with the supposedly "small" pinion gear is bigger than a Ford nine inch. The factory used them behind some nasty engines and they held up just fine. Unless you're building a 500 horsepower or stronger motor you should be ok. All of the pinion gears are pretty much the same size where the pinion nut sits.
There is a reason the factory went with a Dana behind a stick with a "nasty engine".
That said, the 742 survived just fine behind the warm 413/stick combo in my 64 300 with N50's.
