Hey Totalmach1

As you're probably figured out the Packing Slip feature is closely tied to the Invoice so yeah it's not so simple to do what you want.

However, if you draft an Invoice (without sending it) you can create a packing Slip from there.

Now you can actually alter or "play with" the quantities on your Invoice so they match the Partial Delivery. Then print your Packing Slip and change the Invoice back to the full Quantities.

I would recommend you actually attach a PDF of each Packing slip to the invoice as you go so there's no ambiguity.

You could even use the "Service Date" field in Quickbooks to make multiple lines for all the deliveries so it's clear as a bell to both you and your Customer.

Let me know if I'm on the right track

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Thanks
McBride Bookkeeping