Are the OEM wheel locks not all the same? I bet you could go to a dealer and borrow one. If the car is new to you, check the glove box and cubby behind the passenger seat for the key. If you bought it from a dealer, call them up and ask why they didn't include the key.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |