Ok, first things first, peel off the door rubbers, careful not to break em cause they're buggers to find good ones at a wreckers.
You will need to undo the two little screws at the top of the door (pic 1) and then this bolt about halfway down the inside of the door (pic 2)
This will loosen the pillar in the middle of your door. Undo the hex head bolts holding your window onto the cables, slide your window down out of the way, then completely loosen the pillar nuts and remove it.
Your quarter glass should now slide out.
Take it easy mate.