1998 Chevy Tahoe removing oil cooler lines

Hello I have a 98 tahoe 4x4 with about 111000 miles. My oil cooler lines are leaking, so I bought both the upper and lower lines but can't figure out how to remove them from the bottom of the truck. I can get them disconnected from the radiator but it seems like the space is too little for me to get the bottom lines off. How do I do this? Is there a special tool?