I have the Hella Turbos too. They're very power efficient compared to the fans I had. But a lot more flimsy.
I currently have a temporary arrangement with one fan mounted on a large spring clamp with a long cable and a cigarette lighter plug on the end. I clamp it to the the top rim of the doorway into the V-berth. It's simple and effective, but is in the way when you're moving around, and you can't close the sliding door.
My permanant plans are to mount two of them on the V-berth side of the bulkhead, one on either side of the doorway and up high.