Inch, FWIW, I once transported a 500# Virago in the back of my Ford F150
and it was off to one side of the centerline. It made a very large
difference in stability as opposed to transporting one straight up in
the center. Now, that's on the back of a truck with a much higher
center of gravity, so I'm sure that it exaggerated the condition. But
your MC is 200 to 300 pounds heavier than that. If it were me, I'd be
concerned that I could ballast it with enough weight on the other side.
Then again, with an FL in a six-foot wide trailer, it can't be very far
off center anyway, can it? May not matter.