How do you replace the heater core on 1999 Chevy Prizm?

To replace the heater core on a 1999 Chevy Prizm, first, disconnect the negative battery cable and drain the coolant from the radiator. Remove the dashboard to access the heater core, which involves taking out various components like the center console and other interior trim. Once you reach the heater core, disconnect the hoses and remove the mounting screws to take out the old core. Install the new heater core by reversing the removal steps, ensuring all connections are secure and refill the cooling system before testing.