How do you replace thermostat on 1988 535i?

To replace the thermostat on a 1988 535i, first locate the top radiator hose and remove the end connected to the motor. Take out the old thermostat and use gasket cleaner to remove the old gasket. Then replace the gasket and thermostat exactly as it was when it came out. Tighten up the radiator hose over the thermostat.