How do you replace heater core on 94 Mercedes e320?

To replace the heater core on a 1994 Mercedes E320, first disconnect the battery and drain the coolant. Remove the dashboard and the center console to access the heater core, which is located behind the firewall in the engine compartment. Carefully detach the hoses connected to the heater core, remove the mounting screws, and replace it with a new unit. Reassemble the components, refill the coolant, and check for any leaks before reconnecting the battery.