Carron Phoenix Mixer Tap Leak!! Help!!?

Hello, I have a swan neck Carron Phoenix tap and there is a leak coming from the base and where the neck joins the base. The leak is constant and is even worse when you turn the tap on.
I have heard there is an allen key hole on the the tap but I cannot locate it. I have removed the little blue & red sign on the tap but there is just a hole, no allen key hole.
Can somebody please shed some light on how to take the tap apart. I am guessing it is a washer that needs replacing and would prefer to do it myself as Christmas is fast approaching!!!

Thank and much appreciated.