We just decided Tuesday that we really can survive today if we just unplugged them. A couple of interfaces would go away, and some of the automation. So it would be a bit more work for both users and IT people but it would be do-able.
It turns out the HP3000s just shuttle all the data into Great Plains anyway. So "writing the accounting package" really just means writing the rules to automatically trigger input to Great Plains based on current status of the order, rather than relying on users to know that they have to cut an invoice.
We'll see.