How do you repair a vacuum leak in a 1968 firebird 400?

To repair a vacuum leak in a 1968 Firebird 400, first, identify the source of the leak using a smoke test or by spraying carburetor cleaner around suspected areas while the engine is running. Common areas to check include vacuum hoses, gaskets, and the intake manifold. Once located, replace any damaged hoses or gaskets and ensure all connections are tight. After repairs, start the engine to verify that the leak is resolved and the idle is stable.