Not hugely helpful. That would give you the starting point, but the hole isn't "square" to the deck surface. It's angled, and you have to be precise because it has to intersect the lower hole drilled straight back from the water pump mounting surface.
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If I ever need to do this, I'll be welding-up a drill guide starting with an already-drilled block. Something to bolt to a few head-bolt holes, with a hardened tubular bushing to "steer" the drill bit.
I had a service replacement crate engine for a TBI Caprice (part number ended in "151") in my '88 K1500 for eighteen years, until the head gasket popped and blow-torched a gouge between cylinders 3 and 5. ZERO computer tuning, had "as stock" driveability with some minimal extra power.