You can remove the sliding panel with the sunroof still in car.There is a "stop" clip on one of the rails and two plastic plugs (one per rail) at the end of the rails that pull out.
Be aware that the plastic trim at the front of the panel will need to be removed and it is held in by plastic welds (for want of a better description).I did mine recently and had to bond it back in.
I ended up removing all of the foam backing as well which makes the remaining part very fragile so take care.Make sure you use good adhesive,i used high temp spray contact adhesive.
