440 Engine stampings

[James <nyb@xxxxxxx>]

Hello,

This weekend for a bucket full of fun I decided to change the spark
plugs in my 76 NYB.  While I was out there I noted the number stamped on
the bottom of the block to be 4006630-440-9.  From what I can find on
the website this seems to be a 78 number.  Was this code used for more
than one year or does my car have a replacement engine?  What does the 9
indicate?

Thanks,
James