The correct Eccentricity would be 102 mm to center the footing with the concrete core. But you cannot do it because the footing would inset from the exterior finish, which Revit does not permit. 100 mm is the max value that you can enter for Eccentricity. If you can increase the width of the footing a bit then you would okay.
Or, if the 660 mm footing width is fixed then you have to model the concrete and the finish as two separate walls and join them. In such case, the footing to be placed under the concrete wall with 0 Eccentricity.
