Just drill a hole through the square knob on the screw top. The you can find a skinny stick to put in there and use for a lever. Or duct tape a large nail to the side of the container and then pull that off to use as your lever. You could maybe wrap some paracord around the square knob, like on the older lawnmovers where you had to wrap the string around the starting pulley. If you yanked the paracord hard enough it might spin the top off or loosen it somewhat (doubtful, but worth a try).