Change VR Eye mask

Hi,

Is there a way to change the google cardboard viewer by default?
As you can see in the picture the cardboard is showing a lot of black bars on the side that is needed for vr.
However I don’t want that. I would like to have something that is showed in the second picture.
What is a easy way to do this?

I have the same issue, have you found a solution?
@Crossroad1000