Thank You very much @rconner. I will check the site you have recommended. However, for now, i have decided to use a 10"X4" reducing tee and then connect a 4"X3" bushing to it. I can then route the 3" line from there.
Please, does anyone know how a 3" UPVC/PVC run pipe can be connected to a 10" UPVC/PVC header pipe? Is there a 10" X 3" reducing tee or a 10" X 3" concentric reducer made of UPVC/PVC?