Depends, basically there are two 10" drum setups. The early A body that had the 4" bolt pattern and then everything else. I believe the early A body shoes are less than 2" wide, so if you have those you are dealing with the harder to find setup.

Assuming the PO didn't reuse the 68 A body backing plate and redrilled the drums you should be able to use the everything else 10" drum setup.

They say there are no such thing as a stupid question.
They say there is always the exception that proves the rule.
Don't be the exception.