The filter is in the passengers frame rail. Before disconnecting the fuel line you want to take the pressure out of the fuel system. This is done by disconnecting the inertia switch from the electrical system. (That will shut down the fuel pump). The inertia switch is underneath the pass. side kick panel. Once the fuel pump is disabled, crank the car. It will start and then shut down as soon as fuel pressure is gone.
Use a disconnect tool that you can buy at the parts store to open the snap in clips on both sides of the filter. Replace. Connect inertia switch and you are done.
Instead of buying the plastic universal tool you might be able to pick up a better (metal) tool, e.g. at www.thetoolwarehouse.net
Instead of going through all that to de-pressurize the fuel system wait an hour or two (or longer) after shutting down the car. Worked fine for me on my explorer and '99-150. And yes I bought the cheap universal tool from kragen. Works fine once you realize how far you need to push it in.
On my '98 150 I just pulled the fuse for the electric fuel pump while the engine was running, and after a few seconds it quit running. This way all of the pressure is off of the line. I think the hardest part was getting the old filter slid out of the spring clip holder that secures the filter to the frame.