Looking at the 69 assy manual, it looks like the dual horn option was U05, do you have a build sheet for your car or anything else that might show you the options that came with your bird? I know I have standard interior in my 400, but i would have to look and see if that option came with the W66 option (400) or if it was added or someone just put the second horn on my car.
Sorry, about confusion, meant U05 is UPC code for the dual horn option, which you all have the code for already.
