The standard Cummins manifold can be oriented to point the turbo either straight UP or straight DOWN.
You need a standard run-of-the-mill Cummins manifold and orient it with the outlet pointing UP and you will have miles of room for the A/C box.
Alas, Cummins engines on anything but Dodge trucks are NEVER parted out; there are enough punks that can destroy anything driving the Dodge trucks to keep a few engines being parted out most always; these kids seldom have reason to drive/operate anything with the standard manifold.
I searched and finally found the ONLY USED ONE I have ever seen for sale anywhere on E-BAY; I bid high and got it.
For a few years I ran the Dodge manifold oriented in Dodge fashion.
The turbo exhaust-housing was hard against the A/C box, necessitating me to re-mold the plastic box away from the turbo by using a heat-gun and tire-spoon.
I then resorted to removing the plastic box, cutting away the plastic on that side, and replacing it with the bottom of a brand-new Dollar General Store baking pan, also molded for clearance.
This stopped me having to always run the A/C, even in winter, just to keep the box from melting and smoking me out.
In all cases, I covered the box with several layers of that outer-space astronaut ten-million-degree adhesive foil sheeting stuff; it looked
but did nothing to prevent the plastic melting.
You have three options :
#1. Flip the Dodge manifold with the outlet UP.
Fabricate a WEDGE shaped spacer-block on the outlet that places the turbo a little more than straight up.
This spacer will have to have two flange-plates that mate to the manifold and the turbo.
There need not be a plenum divider in this spacer; some of the turbos/manifolds have the divider; some don't.
This spacer will require two turbo gaskets.
#2. Custom fabricate a header that puts the turbo anywhere you want it.
#3 Go to the Cummins store and just buy a brand-new manifold; I bet they are not nearly so expensive as one might think.
I used new studs/washers/nuts from McMaster-CARR and plenty of anti-sieze when I mounted my standard manifold.