How do you change the heater core 88 Ford Festiva?

To change the heater core in a 1988 Ford Festiva, first, disconnect the battery and drain the coolant. Remove the dashboard and the center console to access the heater core, then disconnect the heater hoses from the core. After unbolting it from the housing, replace it with the new core, reassemble everything in reverse order, and refill the coolant before reconnecting the battery. Always ensure to check for leaks after completing the installation.