Hot Rods frame serial number

I've got a 36 ford PU which is a future project so I really haven't done anything with it yet. The title matches the transmission stamp and and the frame number.
I never checked the frame number until today and while they are the correct numbers, the stamping is different from what I assumed it should be.
*18*2486xxx* as opposed to *182486xxx*
I've never heard of a star after the 18. The stamp numbers are the correct ones for that year and not after market stamps. This is an old barn find so I don't think anyone messed with the numbers.
Has anyone else seen a star before and after the 18?

 

A lot of assembly plants and a lot of workers hand stamping all boring day long. Somebody added a little personality to his day.

 

Yup, have seen it several times, also sometimes rear hump stamp is missing stars and/or 18

 

Usually the gap between the 18 and the serial was filled with a special stamp <-> that is so tiny it looks like just a dash.
What you have is just whatever happened on last Thursday after chuck hit his thumb with the hammer. No problem.