Thank you James, accurate description and easy to follow instructions! Now I have my XPS 15z Windows 10 working as I've hoped.
For those using an XPS 15z with Windows 10, I can confirm this method works.
Except, for the driver, I went to the driver page for the XPS 15z (searching using your service tag works, too) and selecting Windows 7 as my OS. After downloading the .exe file, just following the instructions above.