A advise
Sorry brother, I’d take most of that info and throw it in the burning fire place and smile. 2 inch exhaust and Flowmaster 40’s? Oh dear heaven!
Best flowing turbo mufflers;
DynoMax turbo or Summits turbo (Headthrob)
Best chamber muffler Hooker Aero Chamber
Use a 2-1/4 pipe for the 273.
Dual exhaust would be very good to do if that isn’t already the plan. Use an H or X pipe.
What rear end do you have in the car now. IF! It is a 7-1/4, then the upgrade to the Ford or a Chrysler 8-1/4 could be understood if the car is going to see a good bit of “Spirted Driving” exercises. If your just out putting around town, I would not worry.
