You need a special socket to remove them.

http://www.ebay.co.uk/itm/FORD-MONDE...#ht_1744wt_754

Might get away with a deep 21mm socket.

Injectors 47Nm, high pressure pipes 40Nm

Make sure the injectors are square in the head when you fit them.

Make sure you get the codes off the injectors before you fit the new ones.

Fit new injector seals that push into the valve cover.

You can get a proper bung kit (selection of various screw caps and blanking plugs for common rail systems) to seal the pipes etc from Ford, it's very expensive for what it is though.