How do you replace a heater core on a 1987 Nissan Stanza?

To replace the heater core on a 1987 Nissan Stanza, first, disconnect the battery and drain the coolant from the radiator. Remove the dashboard and the center console to access the heater core housing. Disconnect the heater core hoses from the engine compartment, remove the mounting screws, and take out the old heater core. Install the new heater core in reverse order, making sure to reconnect all hoses and components before refilling the coolant and reassembling the dashboard.