Help identifying a GM big block

[Rustybolt]

Hello,
I purchased what I am told is a 1976ish 454. I can not find the ID codes online to identify year and what it was in. The code on the front pad passengers side is CC3303960 and the casting number on the back of engine is I believe 14015445. Can someone help me please?

 

[63Half-ton461]

Does it have 781 castings for heads as that would narrow it down to 73-85 ? or some other head ?