If the passenger side is slightly more convex (you know... "objects in mirror may be closer than they appear"), then it would make sense that the RHD and LHD models are different. The mirrors aren't symmetrical across the horizontal plane, so they can't be reversed.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |