I'm stuck in the same situation for almost completely different reasons. I'm familiar with the Hornet and Rambler and my project is Eagle. I've been using carburetors my whole life and on the I6 series I prefer Carter against the advice of everyone. I am NOT familiar with fuel injection and upon doing so I want to keep my hydraulic transmission and stock electrical harness, which is why I'm stuck using Renix as a crutch. The bad news is that the 4.2L was an intake orphan but that doesn't mean it's not an option for the 4.0L head. The major change with the new head design is that the old 4.2L exhaust is no longer compatible. That seems to be the only important change.
It is far easier work to modify the 4.2L intake to sit proper against the intake ports instead of remachining an injection manifold to have a carburetor mount. Because I'm starting to get lazier than that I'm at the point where I would just suggest a Clifford or Offenhauser intake. It should line up perfectly but there is still work when setting up the intake alignment holes to sit just above the pins. This
thread shows the main issues with setting up carbureted intakes on the 4.0 head. Plenty of forums expand on this pretty good but at least this one is clear about it with good pictures.