George. Are you talking about the 73 Trans Am? Are you sure you have the right headers for the car? As far as I know, on that car, the collectors should aim straight back. How much does it aim towards the subframe? About 3 degrees off straight back or more like 30 degrees?
I bought a full 3" system with Walker Ultra-Flo mufflers from Torque Tech for my 68 Firebird convertible last summer. You can buy as little or as much of the system as you want.
http://www.torquetechexh.com/
For my car, the tailpipes were fantastic. I was amazed how perfectly they fit. The head pipes were short. The bends were accurate, but they were not long enough. Even if I had ordered their "HL" headpipes (longer), they still would not have reached. I simply went to a local muffler shop and bought a stick of 3" pipe.
I later added a Dr. Gas x-pipe. I bought the x-pipe and the 4 in/out pipes. The collector flanges need to be welded on. It fit very well.
http://www.drgas.com/
In hindsight: If I were to do it again I'd buy the Dr. Gas x-pipe with in/out pipes, the torque tech tailpipes, mufflers, and a stick of pipe from a muffler shop.
Ps. There is a note in the torque tech catalog saying that the tailpipes for your car will be a few inches short of reaching all the way to the bumper.
Rick