I used the stock "Hemi style" muffler. It's a little quiet. Dang, Lon (@lkopaska ) has the Accurite system on his 67 Barracuda. I wish I had a video. His sounds sweet with a performance muffler.
I had the Maremount 65 Commando system on my 64 Barracuda, way back in the day, and just fell in love with the straight through system. Accurate systems has an optional straight through muffler now. I would think you could swap the Hemi style muffler out.
