67-68 Dart parts compatibility

I've been told the tail light openings are smaller in 67. 67 has a number of parts "1 year only" including the infamous idler arm. I believe there is a difference in internal door parts some of the window hardware, although complete doors should interchange. The grills already noted. Gas tank mounting is one year only, has one strap across the tank rather than two going front to back. Fenders are different all three years, 67, no markers or reflectors, 68/9 markers/ reflectors were di fferent. The infamous different windscreen/ rear window gaskets/ trim