I did that with a music spring wire. I run 3r trains back and forth 70' between loops at eye level. No switch machines, wires, toggles, electronics or relays to buy, install or fail. No drilling just remove a couple of spikes 7 ties in from the throw bar. Bend a "Z" in the wire end, insert it in the throw bar. Respike the wire along the stock rail then sit down with your favorite beverage and watch them run. It adds a background activity to my 2r RR.
