casting # on the heads is on the two center exhaust runners. The intake also has a casting number 7 digit starting with 9, and a casting date. Carb has a part number, application code and date code, which is a vertical stamp on the throttle side of the float bowl. Distributor has a part number stamped into the housing as well.

http://www.yearone.com/updatedsinglepages/Id_info/pontiacengineid/pontengid1.html

http://www.teufert.net/identify/identify.htm