I did this mod to my car if you are interested. I am in Charlottesville, VA about 2 hours south of DC and will be around this weekend if you want to come hear it/ go for a ride. I covered only the two pipes with lots of perforations in them. Here is a link to the thread I made when I did the mod. I did it all in my garage and just had a shop weld the muffler back shut again.