To remove the catalytic converter, first disconnect the negative cable from the battery, then raise the front of the vehicle and support it securely on jackstands. Apply penetrating oil to the nuts and springs retaining the catalytic converter to the manifold, allowing them to soak before removing the nuts and separating the converter from the manifold, taking care not to damage the oxygen sensors. For 2010 and later models, note that the catalytic converter is integral with the exhaust manifold, requiring the removal of the complete front portion of the exhaust system. Next, in the engine compartment, remove the upper heat shield from the manifold, then detach the manifold and gasket by removing the nuts. For 2010 and later models, unbolt the exhaust manifold brace from under the manifold. For installation, use a scraper to clean all old gasket material and carbon deposits from the mating surfaces of the manifold and cylinder head. Check the manifold for warpage if the gasket shows signs of leaking, and resurface or replace it if necessary. Position a new gasket over the cylinder head studs, ensuring any directional marks or arrows are noted, then install the manifold and thread the mounting nuts into place. Tighten the nuts/bolts from the center out to the specified torque, reinstall the remaining parts in reverse order, and finally, run the engine to check for exhaust leaks.