im interested too as my sunroof seal needs doing so i imagine the sunroof might need to come out? 
if you just wanna change the seal its very easy,open sunroof slightly,pull down trim (it has 4 metal clips) undo 4 screws at the front (2 each side) then 4 screw at the back (2 each side) unclip the metal clips from under the rollers and lift the roof out.
Be carefull as you remove the roof as there is a water trap at the back of the roof that A might have water in it and B can scratch the roof if you catch it.
Once the trim is off from inside the sunroof tho its all very self explanetary and just common sense.

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