I have a schedule 40 4" pipe that is connected to cast iron that exits the basement. For some reason they did not install an outside cleanout when this house was built. The cast iron would be almost impossible to dig down to to install a no hub on because of a small structure and concrete slab that sits in that area. Would it be okay by code for me to have someone dig down to the pipe for me on the other side of the structure and slab and then I can disect the pvc, glue a piece of pvc in each end of a 2-way cleanout, and then connect it to the existing pvc in the ground using Ferco style rubber couplers on each end? If that is not code, what can I do without replacing the whole thing? I've seen plumbers connect pvc to cast iron or clay tile, but I wasn't for sure if it was acceptable for pvc to pvc. If I ever have to have my main service line cleaned, I would like for the big machine to stay outside as my basement is finished. Thanks for any help.