Actually, the rear wheels were placed directly beneath the reactor to accommodate its expected-to-be-significant weight. And the front wheels couldn't be too fa

Actually, the rear wheels were placed directly beneath the reactor to accommodate its expected-to-be-significant weight. And the front wheels couldn't be too far from the rear wheels, in order to support an appropriate turning radius (without all-wheel steering). There was actually a modest amount of real engineering done in support of this thing, and the wheelbase was one of the results of that.