Yes, Z21 could be purchased as a stand alone option, and it included the belt revel moulding, front and rear wheel opening moldings, and (for Coupes), roof drip moldings. If you have any of these, you should have ALL of these!
Of course, things could have been changed and added (or removed) over the years, but check to see if you have screw holes in your wheel openings. That will tell you if you had the wheel moldings. These were only available with the Z21 or Z22 options (although they could easily have been added later on in life, so again, no concrete evidence here).