Question on American Flyer 2206 Crossing lights

Can you get a couple close-ups of the track? And does the signal have 3 wires, or 2 ?

These signals have 3 wires one to each bulb and a common attached to the base.  The picture is one I found, I don't have the trip track so I can't get any better picture.

In the picture above I see 2 ground lock-ons included. But how that ties in with the special track, at a loss. A common Lionel 154c will do the same function.

Restoration of my 2206 crossing warnings is coming along nicely.

The extra piece on the track allows the flanges to close the activation circuit... the contact rail is in the track piece backwards. Unfortunately both lights will light up without alternating.