67-69 Barracuda differences

just curious. hopefully some of you plymouth buffs can tell me. what are the differences between 67-69 barracudas appearance wise? just curious because i wabnt to, in the future(distant future) buy and build one. i like the 68 Barracuda S but honestly i dont know the real deifference.

also, how many here prefer notchback, or fastback? i love both personally and would purchase either one if given an opportunity

thanks!