What is this number stamping on my radiator support? (Not the Data Plate)
 

I was changing out the radiator in my 85 this weekend and when I removed the upper plastic support piece I saw this. Those are not the last 6 digits of my vin.

I tried to do some research and found various other plates with numbers on them, just not one with numbers stamped in the support itself.

https://farm5.staticflickr.com/4396/...6b3c3711_b.jpg