Look at this, six hour quilt by Kay Wood this quilt like a flip and sew. You would have to take the binding off, then just cut the size top, backing, and batting by length . I have done this before and the hardest thing will be taking off the binding. You put the backing and batting together and have them facing the back of the quilt and top fabric facing the top or the quilt pin it on, just make one seam per side, then flip it out , press and do another side, go all the way around then you quilt, then sew binding on.
http://www.kayewood.com/item/6_Hour_Quilt_Book/214