People say these are cast as a sideoiler but not machined.
If we want a more descriptive statement: "Not machined" as a side-oiler but rather as a center-oiler as by Ford Motor Co originally.

And I've looked at the possibilities of rifle-drilling the (side) oil gallery in these, but I concluded it would prove somewhat questionable as to the success rate due to the placement accuracy in the distance of the drilling and the casting material availability outside of the the originally intended requirement. And don't forget the casting bosses for a couple of the lateral oil gallery plugs are removed also, so . . . . . . .
Can any one say if it was the oil cooler as to why they where this way?
We've stripped several of these 427's of their marine equipment and I don't believe this machining was for that purpose. I believe this is just the result of standard machining operation as executed on the non side-oiler FE's, it's just that they don't present the casting material as does the side-oiler block casting which evidently proves to be in the way.

Scott.