Ron my 1968 block, 427 side oiler, has ZERO numbers on it. Well, other than the "standard" numbers found on all 427 side oiler blocks. Like 352 on the front and 427 cast in a couple of different places. I've heard the 427 numbers (like the 352) were also used on 390 blocks and others, so it DOES NOT designate that blokc as a "427". There are no hard core "serial or casting" numbers to speak off. Nothing that could nail down the year of build, or even say conclusively it IS a 427!
So how do I know it's a 1968 427 side oiler? Process of elimination. It was cast to use either solids or hydrualics, that alone means it's after '67. The bore is correct for a 427. It has screw in freeze plugs (GOTTA be 427 now), and it has the side oiler galley feed. I figure 68. Were they still making them in '69? If so, possible '69! OH, it also has the "extra strength" ribs cast into the side of the block that only the late model blocks had. I like to think the "ribbing" is to increase the pleasure!
The heads and intake are what I suspect a "BAR" guy might go with. Those are OEM Ford C4AE parts, 1964!