Easy to do
The mounting bolt patterns won't quite match, but that's no big deal...'cuz even if they did, the holes should be filled and re-tapped to ensure that the new bolts get a good bite and can't wobble. The intake hoses on both toilets is 3/4" ID. However, although the industry standard for head discharge hoses is 1.5", Jabsco is the only toilet mfr who offers a choice of 1" or 1.5" discharge...the discharge on the PH II (and every other toilet) is 1.5". So whether that hose is a match depends on what size your current head discharge hose is. If it's 1", you'll need to replace it with 1.5". If the inlet fitting on your holding tank is 1", you'll need a 1" x 1.5" reducer near the tank. Better yet, LI Sound is not "no discharge"...so as long as you're replacing the toilet, now would be an excellent time to add a Lectra/San (CG certified Type I MSD that treats waste and discharges it overboard legally) too.
