I don't think you need external explanation to get the end. What you do need, if you don't have that though, is a very, very good understanding of classical music, Christian and Jewish mythology (No offence intended; I'm not suggesting any belief is or is not correct) and also a knowledge if Qabalism. In addition, you need to know Japanese culture, various types of philosophy, Freadian psychology, and probably a bunch of other stuff I'm missing. If you understand all that, you could puzzle it out yourself.
That said, once I knew what was going on, and watched it again, there are so many lines that explain what was going on that I can't believe I missed. The trouble is, it's not explicit that it's explaining things.
The beauty though, is how the series melds all of this together on many layers. I prefer to consider everything a metaphor, and focus on the series as a discussion of lonliness and human nature, and a comment of the difficulty of growing up in modern society, but that's just one reading. (The freadian reading, particular, is kind of fun...)
Of course, the average Anime fan is into Dragonball Z. So it's kind of above their heads.
Ok, I'm going to stop now. I said not to get me started. I write essays on the series in my spare time, you see, so I think you'd all be best off if I just shut up. If anyone does want any part of the series explained though, ask me.
