Only the number 697 track trip should be used to throw Gilbert track switches. Instructions for use are on p25 of the Gilbert instruction book available online at americanflyerexpress.com. If you have the same K Line book I do the 697 instructions are included in it as well.
These trips are carefully adjusted using the knurled knob so only the engine will actuate them. The engine can never be parked on the sections of track that have the 697 attached.