Great memories from that video. Hot August nights in the 60's.
It is said that the best exhaust note is a tossup: Ford Flathead V8 running through dual Smithy mufflers or the Mopar 273 Commandos.
@WV64Signet
TTI makes the Commando single exhaust system complete bolt on. Do it. I wish I had done it on my build ( maybe I will).