Actually the years are 67 and older or 68 and newer,I found out while building a Hemi Dart about 19 years ago that the 1967 shock towers had to be moved back to accomodate a Hemi. The 68 and later are a smidge wider. You still cant get your hand between the valve cover and the fenderwell on 68 and ups. I still have an offset brake block if you need one to move that master cylinder.
