I just looked at my Z in the garage, along with some other photographs of OEM fenders, and your fenders don't quite look the same. I think the OEM fenders slope down a bit more toward the outside. I could be wrong, or the angle could be playing tricks on my eyes, but I'd put my money on aftermarket rather than OEM.
CURRENT RIDES:
1988 Tri-Z 350 Twin
1985 1/2 Tri-Z
1984 IT490
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