Replace the thermostat on a 99 Malibu?

Should be located in a fremovable housing at the engine end of the upper radiator hose Drain about 1 gallon of coolant from the radiator Remove this housing Note how thermostat is installed Clean both surfaces Replace thermostat and gasket Replace housing Re-fill coolant slowly to prevent an airlock Start engine and look for leaks Run engine to normal operating temperature with heater on Re-check coolant level Should be located in a removable housing at the engine end of the upper radiator hose Drain about 1 gallon of coolant from the radiator Remove this housing Note how thermostat is installed Clean both surfaces Replace thermostat and gasket Replace housing Re-fill coolant slowly to prevent an air lock Start engine and look for leaks Run engine to normal operating temperature with heater on Re-check coolant level