318 carburater

getting the super 6 set up for my 225 slant 6 - automatic - now i have been told to get an early 318 carburater for this super 6 set up cause these latter carbs on the super 6 were set up more for smog control - had unnessesary ports ? - i am trying to figure out what to do here and possibly locate a GOOD CARBURATER REBUILDER -