This shows how the vents were originally designed to fit. The smaller diameter vent opening goes on the DS, note it calls out a bushing for that vent.
https://www.flickr.com/photos/advance-design_parts_co/31285149207/in/album-72157631872034068/
Here you can see the different diameters in the hoses, vents and bushings.
https://www.flickr.com/photos/advance-design_parts_co/8129443808/in/album-72157631868452754/
https://www.flickr.com/photos/advance-design_parts_co/8129443974/in/album-72157631868452754/