Thanks for the explanation.
Basically what you are saying is that you need a meter with two voltage coils, and have each coil connected between the neutral and each hot leg. I would imagine that the neutral would get connected to the sideways fifth terminal, instead of with a standard 120/240 v where the meter is not connected to the nuetral at all (one voltage coil that gets 240, connected to L1 & L2)
That makes sense. Thanks again.