How do you replace the evaporator coil in a 1985 S10 pickup?

To replace the evaporator coil in a 1985 S10 pickup, first, disconnect the vehicle's battery and drain the air conditioning system to remove refrigerant. Remove the dashboard and the heater assembly to access the evaporator coil, which is typically located inside the HVAC box. Disconnect the old coil's refrigerant lines, unbolt it from the housing, and replace it with the new coil. Reassemble the HVAC system, reconnect the refrigerant lines, and refill the AC system with refrigerant before testing for leaks.