Update: Scott made the crankshaft-mount fan adapter, so we mocked up the radiator and fan positioning.
Pulling the radiator as far forward as we can get it, using a stock harmonic damper*, the crank-mount adapter, a 3" fan spacer, and an aftermarket fan, here's what we see:
This works, but setting the rad further back would give us a nicer hoodline.
Here's what we see if we swap in a 1" fan spacer, push the radiator two inches back, and lower the rad another inch or so. (It's still above the scrub line.)
Now we have more than enough "headspace" to set whatever hoodline we want.
You'll notice we started playing with the upper rad hose in that second photo. I ordered a Dorman 902-3011 water neck the next day. Maybe that, plus a 90-degree-bend hose, will do it. (Pat says it can't possibly be that easy, but he's been fighting his flathead V8 generator mount, cooling fan, radiator inlets/outlets/ports, hoses, and hoodline for a month, so I think he's kinda traumatized.)
* Assuming the adapter-facing surface of the Romac sits very close to that of the stock damper - and that feels like a pretty safe assumption** - the radiator can go here without any more head-scratching. In the unlikely event the Romac doesn't cooperate there, we can, in order of increasing inconvenience: swap in a half-inch fan spacer (easy), shave down the adapter (slight cringe), or make a completely new, thinner adapter (ouch).
** Famous last words?