Here are a few photos of a Bell 407 Overhead Panel that we made recently.
The dimensions for the unit which is shown here are actually the same as our standard Bell 206 Overhead Panel, as the two panels are going to be interchangeable within the simulator for which they're destined.
Each of the circuit breaker positions has been designed to accommodate either a real circuit breaker, a dummy circuit breaker, or a toggle switch - or, where there's no hardware to be fitted, one of the blanks.
To change the hardware configuration (e.g. replacing a dummy breaker with an operational one) is simply a matter of removing the five screws down each side of the panel to allow access to the mounting plate upon which these are all fitted.