'57-'59 radiators are considerably wider than '54-'56. The radiator cap is at the extreme left side of the top tank on '57-'59, it is centered on the '56. The '54 uses a smaller lower hose than '55-'56. The pre-67 Mustangs had 6s or 289 V8s that were easy to cool, so the radiators were sized accordingly. In 68 big blocks were available, so bigger radiators were also available. They probably aren't bolt-ins, but may be adaptable to a '56.
John in Selma, IN
John - "The Hoosier Hurricane"
