My brother was mucking about with my sunroof last night, and worked out that you can pop the glss right off, giving the benefit of cars with the sunroof that slides right back (as mine onlys pops up)
Was nice and easy to do too, if you look at the lever on your sunroof (this is on an 03 reg by the way) there is a little red button, push that in and there is a bar which pops out, then tap (i hit it) the handle up, and it pops off a clip, then lift the glass right up and it slides out of the bits at the front, and you can then take the glass right off the car (stick it in the boot or back seat)
Just thought you would like to know if you didnt already know.