alrite, ive done my rear wiper and what i did was to loosen the actual wiper arm and centre it. only problem is that you cant use the wiper coz it just goes down 1 half of the window and onto the boot then it gets stuck!! also scratching the boot in the process (which iv got 2 have polished out)!! the only way round this i thought woz just not to switch the back wiper on, but after having the main wipers on for a period of time, the rear wiper automatically operates, so theres no way round it unless you disconnect the motor - too tricky for me!!