How do i change the the heater core in a 2007 Tahoe?

To change the heater core in a 2007 Tahoe, start by disconnecting the battery and draining the coolant. Remove the dashboard, which involves taking out various trim pieces, the center console, and the airbag (if applicable). After accessing the HVAC unit, disconnect the heater core hoses and remove the heater core from the assembly. Install the new heater core, reassemble the HVAC unit, and reconnect everything in reverse order before refilling the coolant and testing the system.