[Stuweatherman]

It is possible to fit a gear diff in the centro box, i've done it and ran it today with no problems. You do have to grind out a lot of the gearbox tho, i put the bearings in then used a dremel to take it down to the level of the bearing. You will also need short chassis to gearbox screws and the lower rear shock tower screws need to be just long enough to go just into the gearbox case and no further as any longer than that and you'll bind up the diff.