I thought this was an intriguing question, so I did some research.
Interesting reading there.
An ISO standard 40' shipping container appears to be 39 feet 5 and45/64 inches long, 7 feet 8 and 19/32" wide, and 7 feet 9 and 57/64" high inside.
Now, using my own bus as an example:
Height: 9'10" at rear axle
Width: 8'0" at outer edges of rub rails
You would most likely need to reduce the height and width of your bus to squeeze it into the container.
Now, removing the rub rails and mirrors and wheels might just accomplish that. I'm not sure how you would get it into and out of the container without scratching it then. Also, you would want to secure it within the container.
How much is flat deck shipping in general? I've been curious about that. I'm guessing most shipping companies wouldn't let you live aboard your skoolie while in transit...
I thought most of the kneeling systems in city buses was done via air suspension, but I could be wrong.
Keep up the good work bringing new ideas to the forum. I've enjoyed reading your threads and getting ideas.