I finished it (see Part 1 for context). Most of the delay was in getting the hang of structuring the parent project, and the relationship between the 2 project.json files.
So given a project ShippingContainerApp, a structure like this fits the bill, where SCS is ShippingContainerSource, and SCT is ShippingContainerTest. Also see the repo here:
Anyhoo, you can find the full working project here: https://github.com/aadennis/DotNetCore/tree/master/ShippingContainerApp
Back to the beginning again…