Specific Centipede original cabinet build query

[Cloakandmail]

Hi,

I am building my first scratch cabinet and it will be as close in construction to a Centipede upright as I can reasonably get it.

I have a template for a piece inside the cabinet that the top of the control panel sits on and is placed under the monitor. I know where it goes in the cabinet, that is not the problem.
Try as I might after watching countless videos and studying various images of people restoring centipede cabinets, I cannot work out the function of the the cut out I have circled in red on the attached diagram.

It has now become personal :-), please can anyone with an original cab put me out of my misery. Does it do anything? Thank you.

[bperkins01]

I didn't pull my bezel out..  but part of the monitor frame sits in there.. 

[Cloakandmail]

Thank you so much bperkins01.

I really appreciate your quick response and time to take that photo. That has cleared it up nicely.