First welcome to the site - hope you find the site helpful
Just saw this. My day's car is 165858 and was made 5 days later. DSO or Kansas City.
Just a mention - we really don't know when these built, assuming that you got your date from the door tag/plate, that date was a guess made by the office at the plant were the order was first received. Examples of production suggest that date can be off as much as three weeks earlier or later - pretty wide range
Again... welcome to out site