Anyone swap HVAC unit from donor?

I dug an AC box out from under the dash of a '98 Ram to do this. I like the idea of using the entire system (as much as possible) as it is engineered to work together.

I've done some mockup stuff, but not much else. There is a pretty big notch to the firewall of the truck and the box follows that so there are a couple of inches between the box and the middle of the firewall in my Duster. And I am nervous about one of the vacuum cans and it's proximity to the gas pedal. I think it will work, plan to forge ahead at a later date regardless. I asked the newest owner of the car @BadAss71 built about the gas pedal area and if he had or could take a picture but never got an answer.

As a comparison, I had a '63 Valiant I was going to swap a later A-Body AC box into and it was looking like the box was going to need some mods around the column/wiper motor/gas pedal area to fit. Don't remember the exact issue, but I remember is was due to the width of the box. Due to that, I doubt the Ram box would fit in an early A-Body without having to cut and rebuild the box some.

The other thing I did was figure out the vacuum cans and work out a system to run them using a later A-Body AC control module. It isn't perfect, I think heat will only work on floor mode and AC on ducts (whatever those will be). But I think defrost is both heat and AC so that's good. I'd have to look back at my notes. The issue was which ports are open depending on the lever location so there was only so much I could do with it. I know I didn't want the round knobs from the ram in my dash, they looked too out of place for me.

I might add that the Ram controls are straight up and down (and curved, I think), but certain Jeep GC's used the same (or similar) AC box and their controls were horizontal. Might be easier to make those work if someone wanted to keep the OEM controls and put them in the general area of the current controls. Just an idea.