72' 340 Abody manifolds in early Abody

Has anyone had success with using the larger V-8 exhaust manifolds from a 67-76 on a 63-66' A-body with power steering and 904auto?
In my case- 72' 340 manifolds like the ones in the picture on a 318 in a 66' Barracuda.

I'm removing the manifolds on my 72' Demon 340, 4-speed for a set of Doug's headers and while the 318 is out of the 66' Barracuda- I can remove the 273 manifolds factory style manifolds and put on the 340's for better breathing. (new exhaust is going on at the same time.)
This was a stock photo I grabbed off E-Bay. The driver's side looks correct but the passenger side in the picture looks small. I can't see the casting number to see if it is a true 340 / 360 manifold... but you get the point.340 manifolds.jpg