Partner Function for address only

Hi gurus,

I need to create for my client two partner functions for address printing only (Lets call them B & C)
These will be neither sold-to nor ship-to, but will be for addresses only (to be printed on certain documents)

Once created, some 3rd party customer accounts will be assigned to these partner functions

After creating these (B& C) , I need to assign to these to another sold-to party customer (lets say A)

Finally, when a sales order will be made, it will have sold-to (A)  and assigned partners (B & C) for addresses

Which existing SAP partners, I need to copy from for creating B & C?

Thanks,