How do you replace the thermostat located on a 1992 Ford Ranger 4 cylinder?

To change that thermostat you need to follow the top radiator hose to the motor from the radiator. It will lead to the thermostat housing on the block. The housing will be anchored with (2) bolts to the block (I think). Take the housing off and the thermostat is housed inside.you will have to replace it with a manufactured suggested thermo(probably 180* or 200 degree thermo).