Building on everything done so far, this is a fairly easy part. Again, orientation of the units is crucial.
Step one
Place one of the panels created in Part 13 on top, the largest block in the upper left and smallest block toward the lower right. Place the first panel created in Part 11 on the bottom with the small rail fence block in the upper right corner. Sew together.
Step two
Place the second panel created in Part 11 on the top with the small rail fence block in the lower left corner. Place the remaining panel created in Part 13 on bottom, flipping it so that the largest block is in the lower right and smallest block is in the upper left. Sew together.
Quadrants 2 and 3 (upper right, lower left) are complete! Set aside.