Changing your default car's license plate

Am I stupid? I can't find how to change the license plate number of your default car anymore, wasn't it in the garage? If I change it in free roam in the parts config menu it just works until I change map or close the game... Help?

 

If I remember rightly, I set the numberplate design and text in the garage, then just saved a config of the vehicle and set it to my default
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Atleast that seems to have worked for me

 

I just can't set the text in the garage, there's a tab where I can select the numberplate design but I can't find where I'm supposed to change the text...

 

It's on the right, in the paint tab.

 

Well damn, that's hard to find...

But it worked! Thanks!