I don't think that is possible with javascript. Anything that is going to be displayed would be displayed inside the browser's window. Even if you change
Code:
w_x=(isNS)? window.innerWidth-5 : document.body.clientWidth;
w_y=(isNS)? window.innerHeight : document.body.clientHeight;
To display the arrows somewhere else, the browser will just resize to fit them in.
Plus, it might not be a good idea to have the scroll arrows outside of the browser....what if the user's screen isn't as big as yours and they don't see the arrows in the same spot as you do?