Best way to capture live screen actions on MD4-7

Just wondering what the best way to capture a demonstration of the functionality of the display is. Is there any way to mirror an MD4-7 display from a live system onto a computer or video stream or is my only option to set up a simulation? The main issue I have with the simulation option is that I have a multi-master system, which communicates over J1939 and there is a lot of data to link between the two to make a functional simulation, plus many of our functions would be difficult to demonstrate in a simulation since there are complicated relationships between multiple I/Os. Thanks