My guess is that as the tractor gets smaller, the cab seems proportionally larger, since it must house a human being, regardless of tractor frame size.
Look at a cab on a BX Kubota (aftermarket I suppose) and they really look large compared to the tractor.
I assume you are referring to the B3030 cab version... /forums/images/graemlins/smile.gif
Sometimes it helps if you put a link to the picture in so we can judge for ourselves, or at least tell us where to go look! /forums/images/graemlins/grin.gif Otherwise, we don't have a clue. John