How do you replace 1985 Chrysler new yorker heater core?

To replace the heater core in a 1985 Chrysler New Yorker, first, disconnect the negative battery cable and drain the coolant from the radiator. Remove the dashboard and any components obstructing access to the heater core, including the heater hoses, which should be disconnected from the engine. Replace the old heater core with the new one, reassemble the dashboard and components, and refill the cooling system with coolant. Finally, reconnect the battery and check for proper operation and leaks.