Hi. I don't know the block you are referring to. However, if I understand your goal, you want the finished block to be bigger so you can trim it down to to the intended size of 6-1/2 (which will be 6 inch when finished). Again, not knowing the block, you need to add your extra 1/4 length to the OUTSIDE pieces only. I.e: If A, B, C are sewn in a horizontal sequence, then only A and C should get the extra 1/4. That will allow you to trim off the OUTSIDE of your block and maintain the original scale of the inside fabrics. I hope I understood your goal and that this helps!