old school

they make thrush hush mufflers now. Im thinking due to the design they would be quieter than the normal thrush turbo muffler.
http://www.thrushexhaust.com/products.html

not my car but he lists thrush hush mufflers in the description
[ame="http://www.youtube.com/watch?v=1eZ64wRihxk"]YouTube - 1969 426 Hemi Dart[/ame]