Ardour doesn’t talk to your audio interface directly at all. JACK is used for all audio I/O, whether its going to/from audio hardware or other software (or over the net, or whatever). So the first task is to see if you can use the device as a basic audio interface, meaning that ordinary, desktop style apps and utilities can make noise with it. If they can, JACK will be able to use it. And then Ardour will use it pretty much automatically.
The bad news: I am reasonably certain that the MBox2, like all Digi-branded h/w, requires proprietary drivers in order to function. No such drivers are available on Linux, which is a Digidesign’s choice.