Editing the size of the letterbox panes?

[stevedroid]

Alright guys, I know this is an odd one, but is there any way to edit the size of the letterbox panes? E.g. when the game goes into a conversation, or an in-game cinematic, is there any way to change the size of the black bars at the top and bottom of the screen?

 

I've looked around in the GUI files, but I haven't been able to find anything yet.