Scott - Mine draws water from from the same line that comes from the back of the boat for my front live well (at least that's the way it looks). I see from the picture of the PT175 that your only livewell is in the back, that means you'll have to run the plumbing all the way under the decking to the front, that could be tough. I would definetly NOT drill thru the hull, too much chance of leaking and changing the dynamics/integrity of the hull. You'll probably have to take some of the decking off to get to the proper places, that will definetly be a BIG Project.
Your other choice might be to do what I did in my Jon boat - Buy a small cooler, a 12v aerator kit and just plug it into the 12v outlet by the console. It's not "installed" like a baitwell, but it is removable (you could even build some kind of mounting braket infront of the console and run a second 12v outlet flush on the front of the console.
Just and idea to keep you from tearing up your new boat decks.