Mufflers VS Catalytic converters

[Nima]

Hi:
This might be an stupid question but I have to ask. I know catalytic converter are generally more restrictive than mufflers and they can cost some HP and maybe torque, besides I think they are more expensive than mufflers. My truck, being a 1967 and carburated, has this old car smell. I can't get rid of it doesn't matter how much time I have spent on tuning. I wanted to ask if catalytic converter can filter some of that smell?!! If they do, how about replacing my mufflers, which are basic jegs turbo mufflers, with pair of high flow converters? My truck power train is just a basic 350 and 3 speed tranny.
I have a small two car garage and by the time I start the truck and pull it out to let it warm up, I hear the wife that the whole garage smells, and some times it leaks to the house since it is an attached garage.