hack off the rear can right where it splits into the two chambers. One of them is closed and is designed to smooth out exhaust resonations, and the other is just the rear muffler with a turn down exit.
I cut it at the joint and angled my cut so the exhaust went towards the rear of the car. Without the muffler there it sounds great. The thing has to weigh at least 40 lbs and the car is not too loud at all without it. It is how the 540 should have sounded from the factory. very calm at idle and cruising, and a low muscle note through the lower rpms.
best part... $0 if you have your own sawzall... (Which I do)