Why they were widened is not the point here. The fact that they were is. I know the x-member is not designed for a dual exhaust system on the early "A" cars. A little heat will create an oval spot to gain clearance at the X-member. What I wanted was the location of the mufflers and approximate location/routing of the tail pipes over the Rear end. If the routing of the Exhaust system is roughly the same (distance from the drive shaft) from the mufflers forward to about the x-member area then it would just eliminate a lot of custom fabrication. Since I am a lousy fabricator that is a good thing. It was just an idea I had and thought I would bounce it off of fellow members to see if any one had tried it.
413....just saw your reply and thank you very much. Do you have any pictures of under the car? The '65 Valiant I own had a muffler shop bent 2" system under it with 273 manifolds. The engine is a very mildly hotted 318 so the exhaust system was choking it something awful. I have a set of Spit Fire Headers ordered (I am a patient man) and will go with a 2 1/2" system out the back end.
Thanks to all.