Add VSPackages to Isolated Shell

How do you install VSPackages within the VS Isolated Shell after deployed?

Meaning, I have deployed a shell and would like to install a VSPackage we created.  The VSPackage would only be internal and not published on the VS Gallery.

Also, is there a way to add the VSPackage to a location ( i.e. File Share ) in our internal network so others ( internal ) can point to that directory, select and install to their installed shell?

Thanks