I have taken out my tile shower down to the slab. I am going back in with a cultured marble shower pan and maarble walls. The existing 2 inch drain pipe has a bowl shape fitting on it where the old drain screwed into it. I need to take off this bowl shape fitting but don’t know how it is attached. The house is about 20 years old. It may be leaded on. If so, how do you remove an old fitting which is attached with lead. The drain pipe is cast iron going into the ground and the fitting attached is metal. What other means would have been used to attache this?