Before you can even think of disposing the exhaust manifold, unbend the cable that connects the negative battery terminal, then get rid of the air intake duct assembly and the heat shield that was earlier fixed on the exhaust manifold. Remove both the LSB and the HFM plug connections, lift the car and safely install it on jackstands. The front part of the exhaust pipe can now be cut off; the nuts that hold the exhaust pipe to the mounting bracket are best soaked with penetrating oil first, and the wiring of the oxygen sensor on the heat shield should be disconnected. Then, cut off the exhaust manifold mounting nuts, and disconnect the exhaust pipe from the manifold: For installation clean the mating surfaces on the cylinder head, manifold and exhaust pipe by scraping off any debris then using a rag and brake system cleaner to clean the surface further. Inspection to ensure that the mating surface is flat and that there is no sign of chipping, if there is evidence of warping or chipping then probably the two would require to be machined or changed respectively. New gasket needs to be set on the cylinder head studs and then manifold needs to be placed on the cylinder head studs, nuts needs to be tight from center to outer circle with the recommended torque value. Join the exhaust pipe with the manifold then torque the nuts that are tighten an even manner to the standard torque. Perform exhaust leaks check and then reconnect the battery and start the engine once again but before doing so reverse the above steps of removal.