If this is a DP9, I don't think that you will easily be able to create the filler blocks to match. You would have to measure and cut each piece to make the triangles. Depending on how much fabric you have, you can make full blocks, sew the top together, then cut the excess triangles off. Remember that you need MORE than half a block for the filler triangles, so you can't just cut a block in half on the diagonal and use both pieces. You can, however, take the cutoffs and make a throw!