Thanks everyone!
Capt~
My ballast came pre-wired and I would have to cut the wires to mount it externally. I'm not sure I want to do that as it may void the warranty I have on it. I've also managed to hide all of my aquarium periferals and an external mounting would be the exception.
Daugherty~
I do have 2 fans in my canopy (one intake, one exhaust) and two front-facing vents. My biggest concern was the proximity to the overall heat source of my lighting system.