couple of years back before I made a FCG for the upstairs window, I had eyes in the upstairs windows. Just get black construction paper(enought to cover all windows in a room facing the haunt) cut different shaped eyes in a random patten just like warner bros did with bugs. Then cover the eyes with green red and white tissue paper. Assuming you cut the black paper to fit the windows so no light get out around the edges, tape them in place. Use a low wattage light in the room to make the eyes come to life.