Hey Mark,
That's my old hometown you'll be visiting. First thing you should do is reduce your intake of food now so you can indulge whilst in Montréal. Schwartz' is a indeed a must it's on St-Laurent (aka St. Lawrence, aka the Main, aka La Main) near the Portuguese area of the city which has some fabulous restaurants. Some other recommendations would be L'Express on St-Denis, nice French bistro in a great part of town (Plateau Mont-Royal). A couple of bring your own wine favourites are Au 917, on Rachel St. (917 Rachel!) - french cuisine (I must admit I haven't been to this one in more then 10 years, so do some research and La Raclette on Guilford corner of Christophe Colomb - Swiss Cuisine. If you want good cheap and plentiful food, you could go to one of the greek tavernas on Prince Arthur or Duluth (most are bring your own wine). All these are in the same neighborhood.
Can anyone confirm if the Tam Tam is still on at the foot of the mountain on Sundays? If so, this would be a great place to go.
If you like rock music, tune in to CHOM-FM 97.7 as you approach the border. Best radio station in my book. I still listen to it eventhough I left 10 years ago. Speaking of the border, look at a map and consider one of the alternate crossings east or west of 87 as it can get very busy, but maybe in the opposite direction that you'll be traveling.
Keep in mind that the Metro (subway) does not run 24/7. Some of the buses do. Pick up a copy of the Mirror or Voir if you read French. Their the local Village Voice so you'll see what's going on and get some more restaurant recommendations.
L'ile St-Helene (site of the 1967 Worlds Fair and adjacent to the F1 race track) has great views of the city, it's green and you can get there by Metro easily).
Sorry this is all over the place. Enjoy your trip and make sure to post some pics.
Bon Voyage.