Patience my friend! it's just a car and a car part. There is probably a good reason for the "back order". Perhaps they can't get the part across the US/Mexican boader, or the parts plant is withholding shipment because Ford owes them money, or maybe the Ford dealer parts man is on vacation.
I'm joking of course, somtimes certain low use and low inventory items take a special order. and a lot of time.
Have a beer and relax.....heck if I misplace a screwdriver and can't find it I just sit down, relax and think about for awhile and then go take a nap.
Bill