Importing AP Invoice with TAX

We are importing AP Invoices through the AP Open Interface.   In additional to the “ITEM” line the vendor will also be sending the “TAX” line on the invoice.  These invoices are Non PO (i.e. not matched to the PO).  Now while importing these invoices we have following two options:

1. Import single “ITEM” line.  Put the tax amount on the “CONTROL_AMOUNT” field.
   1. System derives the TAX rate code based on the setup.
2. Import “ITEM” and “TAX” as separate line.  In this case we will need to provide the “TAX_CODE” on the “TAX” line.
   1. We are required to default the “TAX Rate Code” or the “TAX Rate Classification Code”