It is right behind the glove box. Remove the inside of the glove box and you will find about 10-12 5/16" screws on top of the carrier assembly. Remove those then the cover. Loosen the hose clamps on the engine side of the fire wall. The heater core will come out of the hole where your glove box used to be. It takes a little work but it will come out. Remember let the cooling system cool down before attempting any repair that involves the cooling system.