Exhaust manifold question

I have a 72 Dart that I am going to be putting a 340 into. I came across a set of manifolds casting numbers 2863553(drivers side) and 3418623(passenger side). Anybody out there know if these are the good HP manifolds and secondly will they work on my application. I believe they were off an E-body with a 340. Any help would be greatly appreciated.