To remove the manifold, you should first release fuel system pressure and disconnect the negative battery cable. Next, get rid of the plenum, injectors and fuel rail, also the serpentine drive belt and drain cooling system. Remove alternator and loosen bracket and power steering pump if equipped. Disconnect coolant tubes and hoses, label and unplug any remaining electrical wires as well as fuel lines. After that remove the rocker arm covers then manifold mounting bolts being careful not to pry between the manifold and heads. Lastly, loosen the rocker arm nuts then rotate out of the way while removing pushrods going through manifold gasket. During installation ensure that their mating surfaces are clean by using a gasket scraper to remove any old sealant or gasket material. Use lacquer thinner or acetone to clean surfaces and vacuum cleaner should be used in order to remove any debris from intake ports or lifter valley. Chase threads in bolt holes if necessary then apply a bead of ATV sealant or equivalent on front and rear ridges of engine block. The installation process involves installing intake manifold gasket, pushrods, rocker arms etc, Carefully lower the manifold into place and install mounting bolts/nuts finger tight; Tighten mounting bolts/nuts in three steps working from center out in a crisscross pattern; Finally reinstall remaining components, change oil filter refill cooling system & start engine check for leaks.