Modeling Cube

Hi Gurus,

I have a planned ship date from the deliveries header....the requirement is to use that as a dimensional charchteristic in the Cube and the users want to see the delivery number as a Nav Attribute of Planned ship date....this is possible only if u model the delivery number as a a nav Attribute of the info object Planned Ship date....is this the right way of doing it, considering that delivery number is a document number???

Thank You