How to rebrand admin?

I am installing dolphin sites for customers but I do not want them to purchase from boonex but me. How can I rebrand the admin panel and remove all links to boonex? All client websites are fully licensed.

I'm not even sure if you're allowed to do that, but hey, let's give you the final answer:

Firefox, with the Firebug extension loaded.

Happy element hunting.

Contact this person: http://www.boonex.com/unity/LyubovL

If what you ask is possible, she would know.  Don't expect to be able to rebrand Dolphin without a hefty licensing fee.