flow direction of tranny coolant lines & add a tranny cooler

'98 Grand Voyager with 3.3 Could someone please tell me what tranny coolant lines are the presure and return lines....this is for the fluid change, to pump the old out. I also want to replace the add on tranny cooler with a bigger one, any suggestions? I'm a courier and haul heavy loads at 200 miles a day. Thanks!

The line closest to the engine is the return. Throw a line on the other end and you wont make a mess.