If you're still having trouble with the bolt, I recommend PB Blaster Penetrating Oil.
Also, I'm sure your exhaust looks a million times better, but FWIW, I've had incredible results using Adam's two step metal polish. It's the best stuff I've found for polishing out scratches.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed |
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