1953 chevy truck only runs hotwired!!

[chevyoutlaw]

My 53 chevy truck will only run if it's hotwired. Without the hotwire it will run as long as the starter is enguaged, but as soon as you take your foot off the starter button, it dies. It also is not charging while it is hotwired. It has a generator and voltage regulator, probably one of these is bad. I just don't know where to start, or how to check. I have a volt meter, but I'm not sure where to check. I've seen some articles on changing to an alternator, that might be the best way to solve the problem. Any advice is greatly appreicated!!