2002 Jeep Grand Cherokee Fuel Filter Replacement

I made an attempt to replace my fuel filter but could not get the lines disconnected.  I did get one line disconnected on the side with two lines facing towards the engine.  Do I need a special tool to disconnect?  I tried with both hands and could not do it.  I read where you must depressurize first, I removed the 20 amp fuse for the fuel pump and turned the engine over until it would not start, disconnected the negative batter terminal and opened the fuel door & cap.  I sure would like to do this myself and save a few bucks.  If it makes a difference this is the 4.0 inline 6.  Thanks for any input.