Electrical Issues... Need help!!!

[toBURKEulosis]

The other day I was driving to work in my 1972 and I stopped and started to roll again when the battery died. I couldn't get it started so I had to get it towed back to my house. Once, there I started looking at the battery and it was dead so I charged it and out it back in and the truck started. So I figured it was just the battery. The following day I started it up and it was warming up and the it died again. I checked the battery and it was dead. So I figured it was alternator. I installed a new alternator and charged the battery and tried to start it this time and the following happens:

1. Turn key to AUX. Gauges and fan come on.

2. Try to start truck it the starter clicks three or four times, and then all power dies.

3. Turn key to off and turn back to AUX. NO POWER.

I took my battery to Autozone and got it checked and it's all good with 100% charge. Also I couple of weeks ago I got a new starter. I don't know where else to look. Please help me out.