I had a big block B body with an auto trans, much like you I wanted to divorce the trans cooler from the radiator, but I did not want to defeat this effort by mounting my external trans cooler in front of the radiator hence blowing hot tranny air all over my nice cool radiator. The answer was to mount the trans cooler/fan unit midway between the axles away from the headers. Worked like a dream, engine and tranny ran cool and I beat the hell out off it every chance I had. Tranny cooling lines were super easy, mounted the cooler to the sub frame connector on the drivers side. Sorry no pic's like a Fool I sold the car.