My reason for believing there actually is a difference is also because the replacement bed sides have this note
Originally Posted by replacement bed side
**Note: 1963-1973 long-bed models will require modifications to panel in order to fit. The front of this panel is shorter than the original long-bed during those years, and will place the wheel well in a different spot.
If it places the wheel wells in a different spot it must not be the same and indicates that the '74 and later models have a shorter distance from the front of the bed to the wheel well.
I would actually like to know for certain if anybody with a post '73 long bed would be kind enough to take a tape measure and measure from the front of the bed to the fender flare along the rust seam and see if it is 36". I have been considering buying a set of bed sides but have been concerned about exactly what modifications I would have to do to make them fit my bed.