I was cleaning my floor on my 71 Mach 1 fastback. That I have had for 1.5 years. Was on the passenger side, looked up and saw a piece of hollow black plastic. It is loose and runs under the dash to the drivers side. I couldn't remove it but as mentioned it is loose and on the drivers side is larger and no opening. I started the car and tested the vents and defrost. Air seems to blow ok.
I have attached a picture. Can anyone tell me what it is for?
I have attached a picture. Can anyone tell me what it is for?