the common setup is :
slot 249 : d2x v8 Final or v10 r52, based on IOS56
slot 250 : d2x v8 Final or v10 r52, based on IOS57
57 has better compatibility than 56, so you really need only the one based on IOS57, so you could install it in slot 249 and that's all you'd need.
slot249 : d2x base57