Snipe and move, snipe and move. MG there to harass if your AC2 run dry. The goal here is harassment at range. You can lay down decent suppressor fire as well as get a few kills in. If the lights come after you it can get hairy - so keep a friend around if possible or at least plan as escape route if you're friendless.
What a troll build. But hell you make me wanna run this one: http://www.mechspecs.com/forum/index.php?topic=3801.0 I think it could be fun and maybe can make some fair scores