Script Runner, Create issue, Hide key of project name

[Kristian]

I used script runner behaviours to get the names of the projects in a drop-down-list  when I create a new issue. If I create a new issue in the drop down list it also shows me the key of the project. 

How can i hide the key of the project, so I can see only the project name? 

[Raynard Rhodes]

Is the "Custom Project" field a "Project Picker" field?

[Kristian]

It is an Issue Picker. There is an project where are issues with an issuetype: Project. I pick these issues with the project names and have them in the drop down list "Customer Office" without the key.