69 Dart Exhaust

With your car, you will have to build your own system. Headers can have different lengths to the end of the collector . You probably have a driveshaft loop (hopefully). A Dana is larger, and has a different shape. Then there's the rear suspension. If you do turn downs before the rear, it will be loud, drone, probably leak fumes into the car, and it will bow dirt up all over the bottom of the car, and on the other cars at any car show you go to. If you bring them out in front of the tires, it will eventually drive you nuts with the noise right at your ear. The ideas already given are excellent. Changing the headers first, so you can do the job once properly is a good idea. Buying the whole TTI kit is expensive, and probably won't fit for the reasons I stated. Summit sells a nice affordable header back kit that would be a good place to start.