Q: How to replace a heater core in a Ford Bronco II?
A: Disconnect negative Battery Cable, let engine cool. Disconnect heater hoses from core tubes, plug hoses. Remove screws, access cover. Remove heater core from assembly. Install core and seal in assembly. Secure access cover with screws. Install hoses to core tubes, do not over-tighten clamps. Check coolant level, add as needed. Connect battery cable. Start engine, check for leaks.