To remove the glass sunroof panel in NAS SWs:
1- Turn the sunroof knob to completely open the glass panel to the limit of it's upward travel.
2- Just behind the knob you used to open the sunroof, near the center of where the linkage attaches to the sunroof frame you should find what looks like the edge of a silver disk. There will be a small slot in the disk.
3- Insert the blade of a small screwdriver into the slot in the disk and pry forward, against the coil spring that should also be slightly visible in this area. The disk should rotate with a slight "click".
4- The linkage can now be lifte free of it's pivot on the frame, and teh glass allowed to settle back to the closed position with the lifting mechanism now hanging into the cab area.
5- The sunroof glass can now be rotated upward at the rear, just like the sunroof is opening, only MUCH farther. Watch the two metal strips that form the hinges at the front edge of the glass. Be sure you don't bind or bend them as you pivot teh glass upward.
6- Once the glass is rotated upwards to be approximately a 90 degree angle with the roof, the glass can be lifted straight upward, separating the glass panel from the sunroof frame.
7- Refitting is the reverse of removal. Take great care not to bind or bend the front hinge strips. When the lifting linkage is placed on it's pivot point, a slight downward pressure should cause the silver disk to "click" back into the locked position without the need to pry it back into position. Then simply close the sunroof as normal.
I find most sunroof leaks on the NAS D90 SWs can be elimiated by keeping the mating surfaces clean.
Follw these steps every three to six months, or whenever a leak is detected:
1- Remove the glass panel using the steps above.
2- Clean the glass panel inside and out, especially the area that contacts the rubber seal, using the glass cleaner of your choice.
3- Clean the rubber seal around the sunroof opening using a weak solution of soapy water. Pay special attention to the areas adjacent to the hinges. Allow the seal to dry thoroughly.
4- Inspect the seal for any cuts. If you find any, glue them together with superglue.
5- Apply the rubber dressing of your choice to the seal and allow it to dry thoroughly. I like to use a product called Nu-Vinyl it provides a long lasting protection, and is not petroleum based so it doesn't damage the rubber, or leave an oily film.
6- Replace the sunroof glass using the steps above.