Do I need to prep or clean the mounting surface before installing this?

Yes. Scrape off any old gasket material from both the header and manifold surfaces with a gasket scraper or plastic card. A clean, flat surface ensures a proper seal and prevents exhaust leaks.

What hardware do I need to bolt this down?

This gasket ships as the sealing component only—hardware is not included. You'll need the factory header bolts for your vehicle, which you likely already have if you're re-gasking an existing header.

Will this work if I'm installing an aftermarket header?

This gasket is engineered for the factory mounting points of your Z or G35. If your aftermarket header uses different bolt spacing or a different manifold interface, test-fit before finalizing any seal.