That 1964 four door hardtop is not as rare as the 1963 fdh. One of the things that is buggered up in mine is those rear windows. For some reason, those 63 windows just get ate up on the inside with the pot metal pitting. I got hold of one of those 64 rear windows, which for some reason hold up much better, and I learned that even though the top part of the frame is completely different, the base can be interchangeable, even though Ford has different part numbers on them. The front windows are a direct interchange.