I was just able to redo an original set of 1970 Gran Coupe seats. There were two matching broadcast sheets in the seats so I knew the Scheduled Production Date (SPD). So, just for fun I noted all the date codes, note where the SPD is in the mix, for some reason this car was built later than hoped for when the order was first entered into the system.

9-06-1969 - Rear seat bottom upholstery
9-16-1969 - Rear seat back frame
9-22-1969 - Bucket seat bottom frame (1)
9-25-1969 - Rear seat back upholstery
9-25-1969 - Bucket seat back upholstery (1)
9-29-1969 - Bucket seat bottom frame (2)
10-02-1969 - Rear seat bottom frame
10-08-1969 - Bucket back upholstery (2)
10-08-1969 - Bucket bottom upholstery (both)
10-12-1969 - A12- Scheduled Production Date
10-14-1969 - Bucket seat back frame (1)
10-20-1969 - Bucket seat back frame (2)