Heres an ad for a 63 firetruck that says to have a 409 in it. It has been for sale for about a month now with no one buying it which makes me belive its just a 348 and no one checked the numbers. Usually anything 409 is gone pretty quick. But from what I have looked at, after finding a 409 in a 66 80 series truck, is that the 409 wasnt available until 66 and in only 80 series truck i believe. if I am wrong feel free to correct wont hurt my feelings but I didnt know if since it was a fire truck they couldve gotten the 409 or not.
http://www.nextechclassifieds.com/listings/view/857894/