Would that include a cassette deck, or a steering rag joint? If you had a '60s pickup truck, would you retain the in-cab fuel tank? "As designed" doesn't always mean "useful in today's world", and these are all examples. The fuel heater was designed into the fuel system at a time in history when retail diesel fuel was not nearly as temperature-stable as it is today. Today's winter blend diesel, esp. when used with an anti-gel additive, don't need the heater. IOW, like the in-cab fuel tank, the rag joint and the cassette deck, it's obsolete technology.
******** i say, my 8 track is awesome!