I just put a 318/727 out of a truck into the old girl and it looks like it will work out just fine! I will have to use a Duster/Dart left side manifold and fab up motor mounts. I thought it would be harder--it fits like it is supposed to be there.
Is there anything I should know before I make mounts? I have learned alot by reading everyones' posts. Not much info out there for swaps such as this.

Looking to do something similar with my 41' plymouth. How does the tranny clear the bottom floor? Have you looked at mid 70's dodge van 360 exhaust manifolds for cheap clearance?

The A body manifolds are the ones. A van doesn't have to clear a steering column.
I'd have the manifolds on before building the mounts.
Here's a pic of the mounts in my 40 Coupe.
If you do something similar, remember that the rubber will compress. Weld them on a sixteenth to an eighth of an inch higher....

Here's a shot of the manifold and column.
You have read http://shadowmtkustomz.blogspot.com/
and the article he copied, right?

Two lines of thought.
1) If you offset the engine another inch or so to the left, a standard exhaust manifold clears the steering column, least it did for us.
2) I suggest you notch and box in the crossmember around the crank pulley, it makes the move to the left easier, and gives extra clearance to make it easier to remove and install the belt(s).

I think we has to do a bit of hammer clearance on the firewall to clear the right head, not much, but a little. Gene

Thanks for the replies. I see that in your pics that you are using magnum mounts? Looks much easier than the spool or truck mounts. I am trying to keep the engine centered and have measured Mopar circle track headers. Looks like this may be the hot ticket! I will update with pics when I get that far.

Ply-Do mounts.
They don't have a website to look at and order stuff. Do a search here and on the HAMB for more info.