I'm putting it in a 68 Barracuda and the steering column is out. I believe the hose will fit above the steering column and in between the brackets in the dash right above the column. The hose will definitely get squished, possibly by 30-50% but I think it would work. I test fitted it with the bracket that holds the column up to the dash and it fit decently around the bracket. Estimating the steering column in there and I think it would work. I'll get a hand from a friend to test fit so I can prove the concept.
This wouldn't work on my 71 Duster. The dash is designed differently above the column and there wouldn't be any room.
Solution #2 would involve a 1" (possibly 1.25" or 1.5") PVC pipe that runs above the brackets above the column and under the wiper linkage. One end facing the driver side, the other facing the passenger side. Attach the pipe in there to the bracket so it's stationary and the wiper linkage doesn't interfere with the pipe. Put pvc adapters on each end to get closer to the size of the ducting hose and cut the ducting hose in half and attach one from the AC vent to the pipe and the other from the other side of the pipe to the box.
Both restrict air flow. I'm not sure how you could do it without restricting the flow unless you ran it underneath the column, which would look tacky.
