Peter,

All you need is a 1/4" 8mm socket, a few extensions and a ratchet and the wire connections are easy. There is a special MB tool for removal of the glow plugs themselves, but all it is is a 12mm deep 3/8" socket with the extension attached. The rearmost one can sometimes be a bear, but it's not necessary to remove the injection lines to access the plugs. I also put some copper anti-seize on the threads of the glow plugs to make it easier the next time out.

__________________
Regards,
Aaron