The only suggestion I could add is that you could make one horizontal strip from the three in the middle that are shorter if this would give you a better arrangement of the blocks. I have a 12 1/1 inch square ruler and I use it to trim all the blocks that are larger but I do not cut off any of the design so you might have bigger blocks. In fact my method is to cut the squares from the interfacing and then pin them to the back of the shirt front and adjust them to center the design. Press them on and then trim off the excess of the knit fabric.