first off remove leak off pipe, fuel supply pipe and electrical connector, then undo and remove the two injector clamp bolts and loosen the injector so it is free to slide in and out. You will not be able to remove it in one piece as the inner wing prevents you from taking it out in one piece.
Put the two injector clamp bolts back in place and just do them up finger tight, or just enough to prevent the injector turning.
Lastly Undo the large nut on the injector shaft, just below where the fuel connections are. It is 25mm IIRC . It's tighter than a German virgin in there.
Undo this and the head of the injector will come off just remove the rest.