I D needed on these 340 manifolds please.

In reference to exhaust manifold with casting number 4006741.
Chrysler parts catalog number is 4006740.
Left 318 exhaust manifold for 70- 71 Abodies is 2951124 which supersedes to 4006471.
Superseded number may fit 72-74 Abodies with 318 engine but can't find any Chrysler documentation to that effect.
The reason it's not in any parts catalog is because it's a replacement manifold with a superseded part number.