I would suggest something like the V-10 cooler like what I run on my 4R100, although with the manual, you will still need to run it through the factory radiator ports because there's no built-in thermostat on the ZF6 for winter driving and without running through the radiator the oil would be far too viscus during the winter.
And for the record, I've made it abundantly clear that I did not intend to break anyone's balls. Everything I have stated is 100% true.