Hello my name is klint and im from Sweden.
I have a pair of cylheads white casting nr:9772652 and C283.
I allso have an intake whit nr:9770274 and 17436572.
Is ther anywone out ther who now somthing abaut this parts.  

I just saw your message.  I went thru my old books. The heads are from a 1963 326 cid. #9772652. I was unable to find #c283. Its possible that the intake is from the same year. prefix 977 was used for 1963-1964.  The 17436572 I believe should be 18436572. This is the Pontiac firing order which is printed on intake manifold. I hope this helps.