V8 mount questions - steering box?

The '62-6 A-body K-members all interchange regardless of engine size. You just need the correct motor mount brackets to swap engines. The only difference I've seen in the '62-6 K-members is the '65 and '66 have holes drilled for the optional front sway bar that came out that year.
The manual steering boxes for the '62-6 have smaller diameter mounting holes than the '67-72 and smaller mounting bolts to match. They'll still swap out as once they're bolted down, they're not going anywhere. Sometimes you have the ream out the holes on the early box to fit the later K-member. Some of the '62-6 boxes were built with bushings (usually the 6 cyl. cars) and some were needle bearing type. The needle bearing one is supposed to be heavier duty.
Thanks, Mark