What do you mean? There are a few different parts and exponentially number of different combos of those parts however the ducting... If you mean A/C vs standard, yes there are numerous parts which with out doubt were superceded or changed with new parts during production - becoming an absolute authority on Air conditioning parts changes during production would be a HUGE research project.
There have been a few A/C cars meticulously restored on this forum... do searches and start reading... there are volumes of info at your finger tips.