I basically copied the song list onto a text document and then eliminated all the ones that I knew didn't stand a chance in the top 20. That got me down to about 50-60, like anth. Then, I went through and made some more cuts, trimming it down to about 40. Then, I managed to get down to 30. Now, I'm kind of stuck. There are so many great songs on the list and I don't know what to cut.
This is actually pretty interesting, though. I've ranked the albums before, but I've never even attempted ranking the songs.
I'm guessing that this is pretty easy for Bob, though, judging by his profile.