The Z is a niche market. It's tough to get any sort of development at this point if it hasn't already been done successfully. Good luck finding an established manufacturer willing to dump R&D and production dollars into a product with little return. Your best bet is to find a competent fabricator that can make a one-off piece for you.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |