Catalytic Converter on a 65 Slant 6?

This may sounds crazy to many... I am trying to figure of ways to have my daily driver 65 Dart GT not smell terrible.

Has anyone added a Catalytic Converter to your pre-smog Slant 6?

Or does anyone have any recommendations on how to make it burn cleaner? I have electronic ignition, new exhaust, it is tuned up really well, has no mechanical engine problems - it just smells like a old lawnmower when I am sitting in traffic.

Do you have your PCV valve and hoses in place and is the PCV valve in good working shape? If not fix that first, then look for exhaust leaks.