The sunroof is held into the tracks by four bolts, one in each corner of the metal base that the glass is bonnded to.

To access the bolts, sit in the drivers seat and look up at each side of the metal base onto which the glass is bonnded. There should be a thin black/grey plastic piece attaced to each side of metal base. It snaps out with just a litle pressure by lifting up from the bottom of the piece.

With the plastic piece out, the bolts should be visible. Unscrew them and the sunroof lifts out. By the way, these bolts allow you to adjust the sunroof height once it is back in the tracks.

Let me know how the tracks replacement goes as I'm thinking of doing the same thing.