I'm just planning for the future and budgeting here, but I'm thinking about running an AQ2200. My Volvo has a stock 120 amp alt. I havent done big 3 or added a battery to the back yet, but I would for sure do that. My main question is, do you think I'll be fine running an AQ2200 (and 75x4) on my stock alt? What, as a rule of thumb, can most people go to (wattage wise) with only the big and an extra battery? Thanks!