I am curious as to how you would install -- or maybe I should say if you would install -- a window air conditioner in a double hung vinyl window. Installation instructions for practically all the ones I've looked at online (GE, Frigidaire, Whirlpool, etc.) use the standard method of drilling screws into the bottom edge of the sash in order to secure the a/c in place. What if you have nearly-new vinyl windows and can't bear the thought of drilling into them? Is it even advisable to put a screw hole in a vinyl sash?