Trans Cooler Placement

Where's the best place on the radiator to put a trans cooler, top, bottom, either side?

I put mine on the lower half on the front. You still want airflow coming in to the path of the radiator without obstruction. I also moved my license plate out of the way so air currents can come through below my bumper and hit the trans cooler.

I also plumbed mine with 3/8" brake line. The steel line helps cool it down during the flow pattern. Rubber line as some like to do it, or steel braid line hold the temperature in...Its a PITA to bend 3/8" hard line but will last you a lifetime when complete