Just look into the triangle holes, that ain't no oil gallery, it's a water gallery. You can even see the water staining on the gasket from the triangular galleries.
I'm not disputing the bold bit; it's this bit that's wrong - "the oil holes are the small round ones closest to the cylinders" I'll show you a pic in a minute of each small hole (in the head) connected to it's nearest big triangle hole neighbour by a bit of wire threaded between the two.
In this one you can just make out the real oil feed into the head gallery, arrowed in black, hole about 4mm dia drilled into the headbolt hole, which you can see is stepped to a bigger diameter just near this hole, allowing the oil to flow up around the outside of this headbolt, blocked by the washer + bolthead at the top end. Told you it was surprising.
ah well that'll terach me to assume the big block oil galleries are the same as smallblock ones! from now on I'll be eating some of this:
