Hi Me,
In the two circles of the picture you will see two ligther looking surfaces, if you look at you car, same place, it will look black like the surrounding blade arm metal. The light surfaces in the picture is were you need to file down the metal, it will be slightly raised on you car. This is the problem with this part. Originaly the two high surfaces keep the blade arm lifted off in the fully extend position. I recently used a eclectric drill and a burr bit ( little tree shaped looking piece)that is for removing metal, to file these surfaces down, and the blade stays in full contact on the glass all the way over.