Heater core for a 95 G.A.

I have worked on many cars. I have not done any heater cores. Can someone help me. I have to replace one. If I can get a diagiam, That would be perfect. If not, Giving me detailed instructions will be very helpful.

first you have to drane all the coolent. There should be a cock on the right lower corner of the radiator as you are looking at your 3.1 well Wait a sec. I own a 3.1v6 So I can only give you info if you have one also. so hit me back with the specs of your grand am talk to you later josh