Poking around under the dash of my non-AC '70 CS Convertible to find out a lot of the ducts are disconnected, loose or missing. My aftermarket radio is visually blocking the area, but feeling around I can tell where flexible ducts should be attached to, but it feels like the entire assembly is loose and just sitting on top of or inside something else.

According to this website https://www.chicagomusclecarparts.co...rdash-ac-parts, it looks like part 3, the windshield defrost connector feels like its just sitting but not connected in any way to part 1 the heater core. I can feel that the hoses (part 2) should be connected to parts 4 & 5, though the driver's side is so stuff its come off.

So my questions are:
- Should part 3 just be casually sitting in/on part 1, and if not how should they be or connect?
- How are parts 2, the hoses supposed to attach to parts 4 & 5? Just slide on or are the clips or clamps? It seems like the prices for parts 2 are high at this supplier, but I can shop around.

What prompted me to look was an exhaust smell in the cabin. There seems to be a leak somewhere underneath which is next on the list.
Thank you in advance!

 

The diagram you reference is for an A/C car. If yours is non-A/C, this isn't the right picture.