Rear fender extension SC/Carrera differences, help

[kgieg]

I'm working on my 1974 911 that a P.O. installed RS rear flares. I noticed on the right side the fender extension was forward by 1/2 inch at the tail light, so I figured the flair was welded on too far forward. I checked right to left flare placement and they are the same. Then I check the fender extensions and the right is shorter than the left. Is there a difference in years for the extensions?