Catalytic Converter on a 65 Slant 6?
if you do this i siggest you look at a 1975/76 era Dart/Valiant to see where the
factory located the cat. You will need to heat shield the floor to avoid burning the car up.
As i recall; 1974/75/76 era cars were catching on fire because at the
assembly line someone got lazy and didn't attach the under floor heat shields.