I just put the TTI shorty's on my 74 Dart Sport with a 360 and they fit very well.
I also have their full 2 1/2" exhaust and it went in without too many problems.
The only thing that I would recommend is check that the driver side tubes don't come in contact with the cylinder head. I have edelbrock aluminum heads and the 2 center tubes hit the head at the bottom edge. I had to grind the head for clearance. I only noticed it when I had to take the headers out and saw that they flange wasn't contacting the gasket on the bottom of the ports. I don't know if it will be the same on iron heads or not.