Import serial numbers when Receiving

We get spreadsheets of PCs with serial numbers as they are delivered, which I used to Import using a Data Connector and Import Rule. However, I thought I ought to start using the Procurement process so set up a Catalog, Catalog item for the PCs and a Purchase Order for the latest batch of 100 PCs. However, when I come to receive them I can only find how to enter the Serial Number by cutting and pasting from the spreadsheet 100 serial numbers one-by-one.

There must be a better way to enter the serial number, especially as Symantec specifically recommend entering it.