Can anyone tell me the proper way and what tool is best for cutting the abs stub to the proper length to attach the toilet flange. I need to install the Toilet, but I first have to deal with the ABS stub through the floor. It is on a second floor and I would have to cut below the floor level. I want to get a straight and level cut and do not know if there is a proper tool to do this or just what the proper proceedure would be.

Thanks Robert