You can do the same thing with just a servo alone. Simply remove the toggle and insert a servo in its place. One end of the wire to the toggle gets soldered to an inverted "U"-shaped brass plate epoxied to the top of the servo case. The other wire gets soldered to a brass strip screwed to the servo arm. This strip is "L" shaped with the short end of the "L" curled under the servo arm and makes contact with the brass plate when the servo is thrown to the closed position. Secure this second wire along the servo arm to provide strain relief for the solder connection.