Heater box
 

Does anyone know where I can find either a brand new heater plenum for a 1970 Mach 1 or one that is used but in good shape? Price is not too much of an issue if it is in real good condition. I am also looking for a dash wire harness, but did not want to have to get a used one. Do they make either of these things aftermarket? No one I talk to can get either of these new.

Call a place in CA called Mustang Parts House...the guy there should be able to get what you need. If he can't get it, they give a call to Delta Bay Mustang.