Ye, I would cut that strip down to 2 pieces of 10x42, then you can either cut 2 pieces of 10 x 26 and join them together to get your width, with the seam in the middle of the small piece or just cut a 10 inch piece off of one and join to the other and then sew to the larger piece. Make sure you remove selveges from the edge you are sewing on to!