um, ive attempted to replace my fuel filter once, and failed... i ended up twisting the fuel line... but i learned my lesson
you need to disconnect the top bit of the fuel filter, fuel will come out, but you can use hose pinch' things(autobahn, supercheap) to stop that.
I actually cant see the picture you tried to upload but, at the bottom of the fuel filter you need to use two spanners, one for the fuel line and one for the fuel filter. whilst holding the fueline nut, start twisting the fuel filter nut.
very important, the fuelline nut is not a twisting nut, so if you twist the nut you wil be twisting the fueline...
Lefty loosy, righty tighty