This is a Boeing 737 APU / Anti-Ice Panel which is as removed from real Boeing 737 overhead panel where it is located. The panel includes the backplate and the front lightplate which we can confirm has backlighting operational from testing within 5v.
The unit could be populated with the addition of the avionics required for a fully complete panel which could then be interfaced with an input card. Note all the avionics would need to purchased separately and are not included in this sale.
Panel is in very good condition for age, and would make an excellent addition to your flight simulator project.