I've been using my four star for a few years but have never used the grilling function. In fact, it's been years since I've actually grilled burgers. We're having 40-50 people over tomorrow. Anyone have tips for setting the left/right pots for different zones, if necessary? What temp am I looking for on the preheat? I'll be doing 1/2 lb patties. I have a habit of overcooking food when I grill, so some timing suggestions would be appreciated.