Thanks for the diagram. So it looks like the cat-back systems get rid of one of those smaller mufflers/resonators, since there seems to be only one small cylinder right at the front (behind the cat), and then the large muffler at the rear.
2012 Ford Focus SE Sedan, Red Candy Metallic Tinted CC, 5 Speed Manual
SE Sport and Winter Packages, 203A Equipment Group, 17" M&P Wheels
K&N 69-3517TS Intake, Magnaflow 15138 Catback Exhaust, WeatherTech 82573 Window Visors, 35% ON-35 Madico Tint