Hello there, @B Reiff.
You can run a report for the Pending Assemblies to know what are the inventory parts you need to prepare for each sales order. Here's how:
You can also run the Open Sales Orders by Item report. To know more how to track the items you build, check out this article: Track the products you manufacture.
I've added this reference page for your future tasks in QuickBooks Desktop (QBDT):QBDT Self-Help Articles.
Please don't hesitate to tag my name in the comment section below if you have other questions. I'd be happy to help you. Take care.