The routing of the trans cooling lines can be done many ways, depending on the cars use. If it is not driven in extream cold areas, it is better to use a completely seperate cooler, and not connected to the engine radiator at all. The engine water temp normals runs 180-210, and the prefered trans fluid temp is 160f. If you are ude the car in mainly warm weather, routing it through the radiator cooler will be adding to the temp, and not allowing the trans cooler to reach its full potential. By running it through the radiotor, you are using the trans cooler to aid the radiator in cooling the engine as much as the trans. Best way if not driven is very cold weather, is to use the trans cooler as a stand alone. As far as how the cooler is mounted, and which hose goes where, it does not matter.
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