SSRS - Stacked Column Chart - Place label outside column

When I create a normal Column Chart, go to Series\Properties\Label\Position, and select which position I want to place the label. Once I create Stacked Column Chart, this attribute seems doesn't work, neither does the SmartLabels section, after I searched relevant articles about this issue, there is a way to enable SmartLabels function by shrinking column width: Series\Properties\CustomeAttributes\PointWidth.