Wana Buy BUT ,Whats the difference in dart convertibles 67-68-69??

Here's the deal; I'm looking at a 67 Dart vert needs a little work,(NEEDS:new top,seat covers,carpet,paint,new engine,but its a solid car, price is $5k but anyway Its a GT . Whats the difference in the years 67-68-69 ? Is one better to have than the others ? Is one year worth less than the others? What else is there to look at?? Is it worth it?
Need advice