Look in the Completions gallery — there is a TD with some forward windows installed. Not sure a single window that big is a great idea structurally though. The pics I have seen with forward windows had two smaller windows versus one big one. That said, the main structural component is the 4 glass layer “arch” formed at the junction of panels 1&2, designed for supporting the roof racks. If I did a big single window I might put in some extra glass tape or even a wood stiffener bar glued in across the top and bottom of the window opening.
Just a thought…
Don