How do you change a Heater Core - 1997 Oldsmobile LSS?

To change the heater core in a 1997 Oldsmobile LSS, start by disconnecting the battery and draining the coolant from the radiator. Remove the dashboard and any components obstructing access to the heater core. Disconnect the heater core hoses from the engine compartment, then unbolt and remove the heater core from the housing. Install the new heater core by reversing the steps, ensuring all connections are secure and refill the cooling system with the appropriate coolant.