Which mvs cab... there is a single slot, 2 slot, 4 slot and 6 slot. Judging by the pics I have collected when making models the 4 and 6 slots have a larger monitor. I don't know if that helps you though.
Also as also stated by tom there are the candy cabs (japaneese) and the normal style.
We need more information.
I have seen a mvs with a 21 inch in it before. Isn't that odd?