I'm guessing that's where it will be going anyway, it's by far the bigger station.... I've been around on the trains a bit, and have only ever once had to go from Victoria station, and then coming back it was Pic I think.

I bet they'll do it from both station to be honest, if not you're actually closer to the ground I think at Victoria....Manchester should be used to visitors by now, with all the international football, so I'm sure where ever you are you'll be able to find you're way, or get direction to the bus stop from somebody.