@rpayne If you want all your messages to have the same logo, I would suggest looking at using another custom utility for your messaging that you can customize how you want. For example, look at tools like Yo, or the older and not quite as well supported terminal-notifier. And actually, you can sort of get there with basic Applescript commands, though not sure how well those end up working when run from a regular Jamf Pro policy. I have a feeling not too well on current OS versions. And I don't think its as easy to customize the icon it appears with in that case.
The other option would be to change the Management Action.app utility's icon yourself as outlined by @emily above. You would just need to make sure to have some kind of policy to either deploy your modified version, or script the change to each machine, and it would need to be ongoing, probably based around a Smart Group based on an Extension Attribute value, so as to catch any re-imaged machines and new systems coming online. You may find this latter option more work than its worth it for though.
