Instance/object override using uvm_factory


I am trying to override the sequence_item instance/object using set_inst_override_by_name . But I am confused about the instance_path (which is the 3rd argument of method) of the sequence_item.
So, How to set the path for sequence_item?
Below is the syntax for instance_override:

factory.set_inst_override_by_name (origional_name, override_name, instance_full_path)

You can use get_full_name() in the 3rd argument .
We tried on sequences using factory.set_inst_override_by_name but unable to override the base sequence . If we use set_type_override_by_name ,set_type_override_by_type and set_type_override_by_type then it is working.