OK I really hope to put this to bed. I have taken 2 pictures. One from the GSR and one from the RS chassis.

Comment #1 the side supports are simply bonded to the roof skin.
Comment #2 The Sunroof 1/16 steel frame is also bonded to the roof skin and only performs one function. To create a lip/"guide" for the sunroof glass to sit in. The sunroof itself is self contained and DOES NOT bolt to the sunroof bonded piece shown.
Comment #3 The steel sunroof "guide" when removed would be hard pressed to weigh one pound (if that).
Comment #4 Guides and sunroof harware are allowed to be removed.

Picture #1 Simple RS roof.


Picture #2 GSR Sunroof car - I wish that I did not paint the roof as the color black is not a seperate panel of any kind.