Depends on the cars history. If the car has been through a number of owners or has an old restoration, no telling what was changed.
The Muscle Car hobby has been going strong since the '80s. May be hard to believe, but back then no one cared about dated components. You knew the part or casting number you needed, bought whatever you found. Even today, I advise that for certain low-production cars like a '67 Z/28. We did one in the late '80s; could not find carb, distributor or wheels. So today it has '68 DF wheels, a Holley re-issue 3910 carb. The distributor was another story. Back then you could still buy new housings from Delco. One famous Camaro supplier had the ability to stamp them so that's what the owner did. Today of course we know there were only a few dates for 1111266 distributors.