You must be talking about the "wall of sound" version of Thrown Down, which is not a single mix at all (that's something which has been mistakingly repeated for nearly a decade now... drives me crazy!). It's also believed not even to be a Fleetwood Mac cut, but instead the song Sheryl Crow produced for Stevie's Trouble In Shangri La album (with Lindsey on backing vocals/guitars) which was held for later use in Fleetwood Mac. Sheryl and Stevie both spoke of a song which included Lindsey which was later withheld for Fleetwood Mac. Many of us on the Ledge have speculated over the years that it was indeed Thrown Down.
Edit: Is this the version you were speaking of?
http://www.youtube.com/watch?v=K66_CQA6Puc