68 Barracuda Formula S 340 car Charging

First, take the current alternator back to Autozone and have them test it. If it works on their tester, the problem probably lies with your car. Second, I would never shop at Autozone. I have heard too much bad about them and their products. I tried them a few times here in Topeka, and was VERY unimpressed. The last time I was there, I tried in VAIN to explain to a clueless girl what I wanted, and wound up walking out.