Cockpit Concepts

Building your simulator
What you need is simulator software, cockpit control hardware communicating directly with the simulator software, and software to present your gauges on external monitors (FsXPand/FsClient)
To achieve this, the Main Instrument Panel is usually self-made, as a part of the cockpit mock-up.

FsXPand offers all you need to show your gauges.
Similar programs may offer complete panels, that can be used in one way only: presenting the whole on a large flatscreen. We do not believe that a realistic flight simulator can be based on that concept. Serious training requires a cockpit with the look and feel of the real training aircraft in mind.
Even a complete panel on one flatscreen for a certain type is bound to fail this purpose because of its rigidity compared to the many differences in actual cockpit layouts and chosen instrumentation, even within one type of aircraft.

Versatility
The FsXPand concept therefore aims at showing the gauges behind your hardware Main Instrument Panel. For that purpose, the gauges can be dragged to any location on your desktop, and sized to the dimensions you need. You can either drag the complete panel over multiple monitors, or display a client program for each monitor used.

Consequently, please do not expect the instrument panel itself showing up on your flatscreens. While the panel itself will be obscured by your hardware MIP, it would make no sense to limit gauge positions by mocking up the actual MIP within the software. It is the gauges only that count.

Details
Consequently, no elements will be displayed that have no functionality.
Basically, there will be gauges and annunciator boxes, like in real aircraft. All controls are assumed to be hardware controls, and mouse functionality will be present only where necessary for configuration purposes.

FsXPand does not offer on-screen functionality that isn't present in a real cockpit. For example, serious simulators have their own radio stack hardware. The radio stack on screen is offered as an alternative for this hardware. The Radio gauges can be configured to show digits only, within your own hardware frames, should you want to build your own radio hardware.