Do I need to replace anything else when I install this gasket?

The header bolts and studs can be reused if they're in good condition and torque evenly. If bolts spin or won't hold tension, swap them while you have the header off — it's the right time.

Can I reuse the old header bolts, or do I need new hardware?

Hardware is not included with this gasket. Inspect your existing bolts for corrosion or stripped threads before reinstalling. If they look solid, they'll work fine.

Should I clean the header and head surfaces before installing this?

Yes — scrape or wire-brush both mating surfaces clean of old gasket material and carbon buildup. A clean surface means better sealing and fewer leaks down the line.