How do you remove the heater box on 1967 Chevelle?

To remove the heater box from a 1967 Chevelle, start by disconnecting the battery and removing the dashboard trim for better access. Next, detach the heater hoses from the firewall, then remove the screws or bolts securing the heater box to the firewall and the under-dash area. Carefully pull the heater box out, taking care not to damage any surrounding components or wiring. Finally, check the area for any remaining connections or fasteners before fully removing the unit.