I have a brand new 66' Barracuda exhaust sitting in a box I bought from TTI. The head pipes change and Mike at TTI said they will sell me just the head pipes for the exhaust I bought to match the 72' manifolds... the issue is I will not know if they actually fit with out major mods until it goes back together. I was just trying to see if anyone else has used these manifolds with success so I can order the new pipes and have them ready for the install when Im ready. .If too much work then I will just shelf the 340 manifolds and keep what I know works.