Cylinder head identification

[HemiTM]

I pulled to valve covers on the Dart tonight to get the casting number. What I found was #2843675, which is a stock 318 head. My question is, what does the number on the little tag across from the casting number stand for? On the passenger side it was 2293 and the driver side was 11148.

 

[Rocky_JS]

2843675 used years 68- 74
prolly date codes, 2293 (2-29-73) however 73 was not a leap year... 72 was.. so the 29, or maybe the 3 is an 8 as 68 was a leap year, are you sure....?
11148 11-14-1968

 

[HemiTM]

I just went and double checked. Those are the right codes that I posted. I am guessing this motor has been gone through. It is in a 71 Dart.