Everyone I'll try to answer the questions about the 2785312 and the 2785614 shroud. I'm not willing to bet my life on the answers but I'll give it a shot. Obviously the 614 shroud came on 340 383 and 440 cars and possibly the 318 shroud not sure about that. The 312 shroud I believe was found on 273 AC cars and 383 cars in 67. The 614 shroud will work on the 67 cars but it is a real tight fit for the upper radiator hose. The 312 shroud repositions the area for the upper radiator hose for more clearance with the 67 radiator. It looks like the upper connection is slightly to one side on the 312 shroud vs. the 614. Hope this helps.
Carl