Do I need to replace the header bolts when I install this gasket?

Bolts aren't included with this gasket. You can reuse your existing fasteners if they're in good condition, but factory specs recommend new bolts for a proper seal on high-heat applications like this. Check your service manual for torque specs.

Should I clean the header and cylinder head surface before installation?

Yes. Remove any old gasket material and carbon buildup with a gasket scraper. A clean, flat mating surface is critical for preventing future leaks on header joints.

Will this gasket fit my single exhaust or dual exhaust setup?

This gasket is designed for the header-to-head interface only—the starting point of your exhaust system. Whether you run single or dual downstream doesn't affect the fit.