I'd try and hang a scent dripper so it'll give the scrape fresh scent every day. Better yet I'd make a mock scrpe next to the existing scrape to challenge the buck doing the srapeing. Let it hang a week so what ever has made the scrapes has had an opportunity to find your scrape and know that someone else is working his area. Then on the day you plan to hunt, a drag line in is a good idea and I'd permiate the air with some BF F-Gland scent before I start rattleing. When bucks fight and spar it stimulate the forhead gland to give off the odor and that might be enough to convince the buck of the area you are the real deal and bring him in.