What to do with siggy blocks

I have three quilts made of blocks from
an exchange. I have signature blocks
for 3/4 of the blocks, 9 each. I want
to use the siggies in the back of the
quilts.

I presume one must approximate the
location of the siggies on the back when
a quilt is sent out for quilting as the
longarmer needs some leeway in
assembling the parts.

Should I make the back in strips the
same width as the siggies, 6 inches, so
I can scatter them? Should I put them
in a nine-patch? If a nine-patch where
on the back should I put it? Any other
ideas? A label will be added after
quilting.

Susan
aka Betsy Ross