[Greg Reid]

Paint the drums red Paul. '66 got red drums behind the Rally 1 wheels. The rusty drums distract from the nice wheels.
It's obvious at a glance that it's a '64 and earlier intake, and from what b-man posted about the casting number, it's a '64 GTO block also.
It is a 4bbl Carter, which would be correct for the engine.... So, what's the problem?
Sounds like a pretty rare and desirable engine to me, even though not as desirable on your car as it would be on a '64...I say RUN it man.