[goatless]

What did the factory use on cars that had "heater delete"? I'm sure the back of the head had a freeze plug, but didn't they just install a cap on the timing cover?

[Ollie]

Come on you guys, bite the bullti and chage the heater core.

Detailed instructions to chage the heater core in a 79 TA with AC

The heater core is removed from the inside. Start by removing the pass seat this will give you more room to work. next remove the center concile. Then the glove box door and box. remove the vaccume can on the pass kick panel and all the duct work along the bottom edge of the heater. Now the ash try, and radio. Looking through the blovebox hole you will see a control cable and two small vacuum lines remove those.
On hte firewall side, You have the inner fender liner outthat is good. If you look on the fiewqall just below the heater fan you will see a stud that is about 2 inches long with a nut on it that is one of three studs that hold the heater box on the firewall. the other two are in board at about the right valve cover. On will be at the top of the evaporator box and the other one will be at the bottom. Remove all three nuts andfrom the inside of the car pull the heater box straight out as far as you can then turn it down and push it down to the floor it will be out.

[79TA455]

Jim Hand's book goes over this....pg 80 IIRC.