Alternator & Voltage Reg? (My 1st 67 project)

[GreenBay1921]

I've been working on a 67 C10 SWB that I bought just before Christmas. It has been sitting since 92. I've been able to get her running & stopping, but she still needs some tweaking & lots of work. I haven't worked on anything (besides brake jobs & oil changes) for nearly 20 years. So try to bear with me guys, I'm not as good as I once was .... So my question is: I have the engine running, but when I take the battery cable off she dies. I know this usually means alternator is bad, but I don't know much about a voltage regulator . Should I just get a new alternator & voltage regulator, or is it more likely just the alternator? Thanks guys.