I keep looking at all the successful, flying rotary engine airplanes that are using evaporator cores and can't help but wonder if this is the hot setup.  Just for everyones consideration, some Toyota's use a standalone water pump that has 2 outlet ports.  These look to be about .7" in diameter but I have not measured the size.  I can't help but consider using this pump mounted 'low' and using an adapter like the guys using EWP's are using.  These 2 outlets from the water pump can be used to run 2 evaporators cores in parallel without fighting with the uneven flow that most other setups deal with.  Advantages are:
1.  LOW mounted water pump (what is the flow rating of this pump?)
2.  parrallel flow to 2 evaporator cores
3.  more even coolant distribution to the cores

Thanks,
Ken Powell