842 Aluminum BB heads cast date?

[rally]

Guys i have a pair of 842 heads. One head has a cast date of 69. The other head has no cast date, i am thinking this head is a service replacement. The only numbers i could find on this head are 5625, the other one is 4025, what do these numbers stand for? Is this some kind of a cast number? Or is it a replacement number they used?