ORIGINAL OIL FILL CAP

[ALLZS]

HOW CAN I TELL IF A OIL FILL CAP FOR 69 S/B CAMARO WITH ALUMINUM VALVE COVERS IS A CORRECT ORIGINAL & NON A REPOP ? THANKS

[x77-69z28]

I know the originals have an S rivet in the center. Not sure if the repop do.
Buddy