As an FYI, the 7 x 8 layout numbers above will give you an 18" drop at the foot and sides with a 12" pillow tuck. Normal pillow tuck is between 10" and 20" depending on the thickness of your pillows. A 7 x 9 layout (finished quilt of 97 x 122) would give you the 18" drop and a pillow tuck of 24". For that you would need another 28 of the 6" blocks. The 5 yards would still work out for the larger quilt (using closer to 4.65 yards).