First look for a mounting place away from the exhaust system, there are places under the bed. The cooler will dissipate a lot of heat even without much air flow because the oil will be VERY hot when the transmission is under a load. On top of many front skid plates are good mounting spots. Mount the cooler in the hot out-put line between the transmission and radiator and it and it will be a pre-cooler. I used a clear piece of hose connected to the in and out cooling lines to find out which was which. After connecting the clear hose have someone start the engine while you watch to see which way the bubbles flow to tell which line is which. An after cooler would cool the transmission oil better but still put too much heat into the engine and be too cool in the winter.

TIP: I have noticed many stock cooling lines need to be insulated from headers and pipes....