Ooh, also, I was thinking as I was driving to my friend's house... if you want the finished quilt to be in the 64" range, then my 5" borders are way too big, lol. I would probably do 2.5" (unfinished) borders, get the quilt to 67" square, or if you want a big border, do 6x6 blocks (54") and bigger borders.
Good luck! :D