Re: Replace 67 Heater Core
1. Disconnect battery and drain coolant.
2. Disconnect heater hoses at engine.
3. Loosen screws at choke housing and position hose out.
4. Remove nuts retaining heater to dash.
5. Remove screw retaining ground wire at dash and disconnect two wires. Remove glove box liner.
6. Disconnect defroster hoses, temperature control cable, defroster control cable and heat control cable.
7. Remove screw retaining heater to air intake.
8. Remove heater assembly from vehicle pulling hose trough dash.
9. Remove both heater hoses at heater core and remove rubber boot from air intake and clips holding both halves of heater togerher.
10. Seperate halves and remove heater core. Reverse procedure to install.
Taken from Chilton's Auto Repair Manual 1964-1971