Plumbers?

For clarification, Redfish, in a residential situation as we're dealing with here you are correct however in many commercial installations they do go in the wall with a wall mounted stool but i think he's refering to the drop that will run down through the wall below as he heads for the existing line at the othet tyin. His closet flange will be mounted in the floor, That is correct. On to the other issues. 422, measure out from the wall/sheetrock 12 " for the center of your hole in the floor unless your useing a 10" unit. Be sure and miss the joist below.
Small Block