worst thing I ever ( !) did to a quilt top was not have enough back material.. don't scrimp or ever think ( perfect fit).. always leave enough for what it takes and more !
Good luck.. really enjoy your top you have ! Plus.. think of the batting.. cotton dense or polyester fibers.. all up to the pile you want afterwards. more pile between stitches iwth polyester fibers.. cotton dense for needle on machine.. easier to manouver..
Ell
things I have learned along the 30 year path.