Will this gasket work if I'm reusing my old header bolts?

Yes. As long as your existing bolts are clean and not stripped, torque them evenly in a crisscross pattern to factory spec per your service manual. Don't over-tighten—aluminum gaskets can compress past the seal point if you do.

Do I need to clean the manifold and cylinder head surfaces before installing?

Absolutely. Scrape off all old gasket material and carbon with a gasket scraper or wire brush. Wipe both surfaces clean with a degreaser or brake cleaner and let dry completely. A dirty surface will cause leaks even with a new gasket.

Can I reuse this gasket if I pull the header off later?

No. Once torqued down and exposed to heat cycles, aluminum gaskets compress and lose their seal. Always use a fresh gasket when you unbolt the header again.