1966 Barracuda headers, fenderwall or not?
I had fender wells on my 66 They are really good for a lot of reasons. Takes about 15 minutes to take them on and off. Leaves lots of room for starter replacement. However tire rubs could be a draw back. I always used a 165-80-15 skinny tire on my car with no problems.
The thing I didn't like was seeing the exhaust pipes go under the front sub frame. They hung low and dragged on everything, also they are more likely to rattle on the frame and body of the car.
I went with the TTI in frame headers now but they are a real pain too! Just like the looks better after installation from the side of the car view.