Stroking a 340 in a 68 Dart GT

If the engine was rebuilt prior to the issues (looks like the car burnt?) then there is a chance that a: the engine is not destroyed (was engine bay engulfed in flames?). If that is still good, the entire rotating assembly is the way to get the longer stroke in it. Rods are the same length, but pistons are very different. I would keep reading.. You first need to know how the basics work before you start adding stuff. And make sure the engine didnt get engulfed in flames. If that was the case, I'd suggest you competely rebuild and re-machine it.