David Knight
Hi Rod. If it's the layout that I think it is I'm not sure you can achieve what you're looking for. From your description I would imagine that the 'ceramic pipe' is actually part of the pan and it's cemented into the soil pipe collar in the floor? Removing the mortar around the pan is likely to be a delicate operation, and assuming that's successful I'm still not aware of a fitting that will do what you want, or even fit without removing the pan which is also often cemented down in place! I would suggest you call out a local plumber that can see the situation first hand and advise if what you want is possible.
