-1 lockable switch
-2 electric connectors or 2 physical connector with composite inputs and outputs of your choice (one connector per end/face)
-Conditioned part 4 controller (see later chapter for Part 4 creation and condition)

-2nd lockable switch for your 2nd cab
-Isolation switches for each connector
-Input (External Master Lock) for forcing both master switches to lock, but will not turn off the master signal (I like to preferably use them for when reverser is not in neutral or you want to have a anti theft switch)

Flip Rule - this is a output that will compare the direction of the master car (this is assuming this unit is a slave unit) and give an output if the train is facing the opposite direction from the master. This is useful for making your trains automatically align themselves to go in the right driving direction or to make your slave unit passenger doors sync up with master unit passenger doors

External Unit Data - a self explanatory output that will pass on composite data as a slave unit to microcontrollers of your choice. E.g. throttle channel incoming from the master car making your unit also apply the same throttle direction. Or another example, a on/off channel dedicated to passenger heaters which will turn on with respect to the master cars inputs

Step 1 - Place the unit down, the 2 connectors down at the ends of your train where your couplers would be. And place the lockable switch/switches in your cab(s).
Step 2 - Make sure your connector and lockable switch are connected to an electric source
Step 3 - Place down your Part 4 controller (ideally near the Part 1 controller)
Step 4 (optional) - Add and properly modify Part 1 for intended permanent connections
Step 5 - Select the Part 1 controller and select the desired operating conditions of the unit (MU, SC, Dual Cab)
Step 6 - Edit the controller and resize the controller to save space (the initial controller was made large for the permanent connections)
Step 7 - Wire up the thing and watch it work
Step 8 - ????
Step 9 - Profit (heopfully)