I think you may need to take the other scraper off. My initial memory of the
process is slightly in error. The 90 degree rotation is part of the actual
removal of the glass. I found a picture I took in the process of removing
the glass that shows how I did it when I changed my wing windows:
<http://blue.foodhammer.net/window.jpg>

The front-upper corner tilts forward and passes to the outside of the wing
window frame, while the rear-upper corner lifts up and passes to the outside
of the upper door frame.

--
John Bange
'90 Vanagon - "Geldsauger"