How do you replace the heater core on a 1997 Ford Thunderbird?

To replace the heater core on a 1997 Ford Thunderbird, start by disconnecting the negative battery cable and draining the coolant from the radiator. Remove the dashboard and the center console to access the heater core housing. Disconnect the heater hoses, unbolt the heater core from its housing, and replace it with the new unit. Reassemble everything in reverse order, refill the coolant, and check for leaks.