How to update Nexus 5 from 5.1 to 6 without data loss and maintain root

[PrimalYeti]

Hey everyone,

Since installing 5.0, i've had my Nexus 5 rooted, and I've been flashing just the OS portion using fastboot so as to maintain all my data (as per this article, aaronhastings.me/updating-to-android-5-1-0-on-rooted-nexus-5/ )

How can I update to 6.0 while maintaining my root and data?

Any help is greatly appreciated
Thank you!