The answer is easy, either the Champs on St-Laurent or a fews doors down at the St-Laurent Frappé
I personnally prefer the Champs, the ambiance is completly crazy when the portuguese play, but the Frappé will be really good too!
Either way get there at least 30-60 minutes before the game if you want a spot! Even earlier if you are with a group!
Wtv you do, you want to be on the main if they win!