I have a leak on my 2000 Jetta

I have a leak on my 2000 Jetta. The leak is from the topside hose going into the radiator on the drivers side to the hard plastic piece clamped directly to the radiator. The leak appears to be from the piece that the hose connects to on the radiator. This "piece" is difficult to remove, very difficult. When the new radiator was put in this piece was taken from the old radiator and it was broken apart from the old radiator because it was difficult to remove. So now we have a small leak from this area on the new radiator but cannot seem to remove this hard rubber piece between the hose and the radiator w/o seemingly taring it apart. How can this or should this be removed? That is the million dollar question. Please Help? Thanks in advance.