How do you Commit the configuration of a Panorama to an existing HA Pair of 5060s?

[Nonno1]

I followed the instructions from “Panorama-Device-Migration-Tech_Note-revB.pdf” using the CLI method to capture the configuration of an HA Pair of 5060 running PAN OS 5.0.11 and paste it to the Panorama running PAN OS 6.0. The Migration Checklist states during the cutover process to cutover 1 firewall first. The document states after deleting the Rules, objects etc. on the FW, when committing the configuration to the HA pair, follow the documented HA procedure to minimize network impact. What are they referring to when they say “follow the documented HA procedure? I cannot find anything referencing what they mean. I figure I should leave the passive FW alone and do the Active one first because when doing a commit on the Active FW it usually pushes the configuration to the Passive FW.

But, What impact does the Device Group have when you set the FWs up as an HA pair in the Device Group? Also, when deleting the items from the Active FW, should I also delete them from the Passive FW?

Another approach that I have read is to rename the objects, policies etc. on the Panorama then commit it to the FWs. What does that do to the existing configuration on the FW? Is there now a duplicate configuration with a different set of names? Or does it overwrite the existing configuration?

Lots of questions and scenarios that I cannot find answers to anywhere.