The horns that are on my 56 GMC 100 Deluxe Cab sure look like they were born there, but a lot can happen in 60 years, and it's looking more and more like they are not, in fact, original to the truck.
They are Delco Remy 759 and 760, and they are the sea shell type with the round dome backing just like my 54 and 55.1 trucks. The 56 GMC maintenance manual, and the 55-57 GMC Master Parts Book both only list the number of one horn, the low note, which is for 56-57 and it's a 305, and the cross- section illustration in the manual looks to be the later type horn that does not have the dome backing cover... I assume then that the correct high note to match would probably be a 306. Can anyone with a 56 or 57 with an original horn, or preferably dual horns, confirm what they have in terms of model number, and if possible snap a picture of how it/they are mounted and what the brackets look like?
