Loving how fast this 3rd clue went from the 2nd one. I'm finished this morning and I'm not a speed demon sewing. I wanted to pass on a hint that works for me. When finishing units like that don't have a total outside measurement. I don't press or trim until the reveal. That way, if I have sewn too scant or too large a seam, it's easy to rip out and adjust. Just in case.