[Caprimaniac]

"One company said they could thread any Delphi Injector. So I might end up replacing them all."

This mean you need the threads....

I suggest swapping to O- ring fuelrail & have easier access to injectors.

In theory, 32 lbs are too small to supply ethanol for a race spec 351/408. Although you might stretch this by fuel pressure.

It'd supply enough fuel for 500 Hp gasoline engine, is my guess.

Seems like your injection setup works well.
Good luck in the race.
RS