The fuel filter is located on the inside left frame rail. You want to make sure the front of the vehicle is higher than the rear to avoid siphoning fuel out of the tank. First you have to relieve the pressure on the fuel system. There is a switch on the passenger side of the vehicle that shuts the fuel pump off during an accident. Locate this switch and remove the wiring harness. Next crank the vehicle and the engine will run out of fuel. Now open the gas cap to relieve vapor pressure and then close it. The fuel filter is connected to the hoses with quick connect hose fittings. There is a tool set that you can buy for about $12 that you will need to take the hoses off. This tool did not work for me because the hoses were too close to the filter. There were other tools available at the shop I went to which were smaller and probobly would have worked but I was able to push down on the button on the hose and pull it off of the filter. According to Haynes there are other methods of connecting the hoses for different years but the quick connects are on my 2003. After you get all the hoses off you can reinstall the new filter. Make sure you push the hoses on all the way and hear the quick connect snap into proper position. Now go back to the fuel pump switch on the passenger side of the cabin and reconnect the wiring harness. Also make sure that the fuel pump switch button is pushed down. If you hit the switch when you take the harness on/off the button will pop up and open the circuit. Now you can start the truck.