There was the main vox track, a overdub track, 3 harmonic tracks & 2 adlib tracks in all if I remember clearly. It was also a very tight delay timed to the music, the overdub is very slightly there to give it a little body, and then the harmonics add the flava lol. I usually try not to pan everything equally, like 2 tracks left, 2 tracks right, cause then all it does is make it sit wider. I usually keep 1 main center, the over dub I would lower the volume, add reverb to it to give it a sense of space instead of panning it, the harmonics are usually panned during mix. I usually just automate them so that I don't have to sit there panning during mixdown.