How to change the text of credits

[Zack]

So i've been working on a Mario Kart Wii mod for a while and wanted to know how to change the text of the credits. (The one with the Staff Roll B music)

I know how to change the text normally for like the menus and stuff, but not this one.

Could someone please help!

EDIT: I know StaffRoll.bmg exists, I just don't know where