Do I need to clean the header flange and engine block before installing this?

Yes. Scrape off all old gasket material and carbon buildup from both surfaces with a gasket scraper or putty knife. A clean, flat surface is critical for a proper seal—any debris or old gasket remnants will cause leaks.

What fasteners does this gasket use?

The gasket itself comes alone. You'll need the factory header bolts that came with your original manifold or sourced separately—mounting hardware is not included.

Can I reuse the factory header bolts, or do I need new ones?

Factory bolts are typically reusable if they're not stripped or corroded. If you're replacing them, refer to your vehicle's service manual for torque specs and bolt grade to avoid over-tightening or leaks.