Reply to "Lionel postwar RCS track rails for unloading on hargraves track"

The item in your picture is wired as follows, starting at the bottom of your picture, first screw terminal is the outside rail, second is the next rail in, third is the center rail, forth is the other accessory rail.  I just placed one of these on my text bench.  I connected the first two terminals and ran a momentary switch (button) from the hot side of the transformer to terminal 4.  This will make operating cars work.  There is no way to uncouple with this track.