Custom Button and Location

[joshabts]

I am creating a custom button for a help desk system that we are already have implemented. However the current Help Desk button already shows in the interface under Help & Support. When I add the custom button it shows up under a heading called Custom.

How can I remove the default help desk button under Help & Support and replace it with my custom button, or at the least, change the location of the Help Desk button to point towards our own help desk system and not Plesk's?

Thanks in advance for any guidance with this!
Josh Abts