I have holes in my 4" lead soil pipe that leads from the upstairs toilet to a vertical cast iron soil pipe.
I have removed the ceiling below the bathroom in question to gain access to the plumbing.
I would like to make this repair with plastic pipe; however, two other pipes join this connection. Both are 1.5" coming from the lavatory and tub. The lavatory connection enters the 4" lead pipe at an elbow directly off the toilet connection. The tub enters at a tee that is adjacent to the cast iron soil pipe.
My problem is: Using lead made it easy to manipulate and facilitate the connections. Plastic is less compromizing and there doesn't seem to be any obvious way to fit the connections with plastic due to the existing angles of the lead pipe and the close quartes.