I'm no expert on mountains, but I do hunt some very steep "hills" on occassion. Its the same and different at the same time. The basics are the same. But the terrain changes your style. Start high, and work your way down. Try to always set up above a bird, or level with it. Shelfs or ridge tops are good spots. The thing that always gets me is how far off you can hear a bird, he may be 600yds accross a valley, that would take you 30 minutes to get accross, yet he sounds like hes right on top of you.