I'm just going to go out on a limb here and assume that 7 foot figure is the body of the carriage NOT the height from top of rail to roof. As a side not theres a Japanese joke buried somewhere in there.
Also it sure seems like you are forgetting that LIM trains have wheels. Sure they dont have a big motor at the center of the bogies to turn the wheels but that doesn't account for much difference in height. Maybe a LIM for the Munchkinland Railway.