Sorry for sounding stupid, but how the hell do you remove the rear wiper arm from a Clio 172cup? I've had the nut off the wiper spindle but the arm wont seem to budge, left some wd40 on it and still no luck! I know its got to come off that way as you cant exactly squeeze the wiper motor out through the bootlid! I just dont want to use too much force and break anything!!