SPOILER! Don't watch this until you've seen the last episode!
When Stephen Colbert talked to Vince Gilligan about the song El Paso used in the season finale of Breaking Bad, he asked if Felina was Jesse or the blue meth, and Vince basically said Felina was the blue meth.. Viewed that way, the song El Paso matches up with not only the scene it was used in and the season finale, but the entire series. Or at least I was able to shoehorn it all in, I have no idea if this is how the creators meant any of this. So I put together the rest of it, just the way I saw it, to the whole song before and after the actual scene from the finale.