I took apart the interior in my challenger and it has the factory sound deadner which breaks easily when bent. I want to make it so the car is really quiet inside and comfortable to drive. Also the insulation behind the rear seat doesn't really help and want to put something there so it covers up the whole opening to the trunk. What are some things I can do to just make it more comfortable and quiet also it will help the sound system. My goal is to make it a more modern feeling.
