I have a 1976 Dart with the 225. I also have a wrecked 2006 charger with the 5.7. Does anybody know how much of the running gear will transfer besides the engine and transmission?

 

Well, the axle will not unless you plan to set you Dart up w/ the IRS set up. I would not use the 8 1/4 rear your Dart probably has (or less) behind the 5.7 Hemi.

I assume you realize the whole electronic/engine management system will need to be transferred as well.