I have a toilet in the corner of the house, the vent is in the exterior wall and runs up to the attic area. Is it possible to attatch the vent after the combination why/tee turns horizontal? This would be at the top of the 3" horizontal pipe and vent up into the exterior wall. Or should I try to lower the height of the the horizontal pipe and try to vent it out the side of the vertical just below the toilet flange?