Easy to fix, add a 5 inch strip all the way around. Should be big enough to send to a quilter or keep and do yourself. Back should be 3-5 inches larger on all sides so you have fudge room. Just when you think it's centered, you pull a little more here and a little less there and it doesn't measure up. Pretty soon, your short on one end. Better to add now and if your going to be quilting it yourself, start from the center to pin. Never cut it off until the quilting is done. Give's you more of that 'fudge' room. Good luck.