Remix of Prusabox Expandable Steel Sheet Holder and centering plate

I was looking for a way to use the expandable sheet holder and still use the modular control panel centering plate. I remixed the bottom control panel covers to relocate the mounting holes so the brackets from the expandable sheet holder would line up.  

Please note: I removed the PI mount from the model. I am using the waveshare 5" touchscreen and mounted the PI directly to that. Also, the front right bolt used to attach the bottom control panel cover under the PI lands right under the bracket. Just install the bracket onto the bottom cover loosely and move it out of the way to secure the front right bolt, then position the bracket where it needs to be and tighten the bolts. There will be a little deflection, but it doesn't cause any problems based on my testing.