When moving a gusset, the only Move
                handle that displays is simply the handle that allows you to move the gussets along
                the bend axis on which the gusset is defined.
            - Click Move in the Edit group on the Sheet Metal tab.
- Select the gusset that you want to move.
- Move the gusset along the bend axis to relocate the gusset to a new
                        position.You can also enter a new location value for the
                    gusset.
Note: When you use the 
Fill tool to fill a gusset, the bend geometry on which the gusset is
                    defined remains intact.