Ok let me see if I can explain how I would do it and have it make sense :roll:
You have all the fabric cut- put in baggies in order of sewing also have a scrap piece of paper - number them from 1-39 after you sew the first two pieces from the first bag pin #1 on that - sew the first two pieces from row 2 Pin #2 on that - that way all the rows are numbers and since the pieces are in order in the bags you should be able to move pretty quick ?
Does that make sense