Close, RBF. In the NG, the left one is labeled "MAIN ELECT" and the right one is "AUTO PILOT". MAIN ELECT "deactivates stabilizer trim switch operation" and AUTO PILOT "deactivates autopilot stabilizer trim operation". A few pages later, "The STAB TRIM MAIN ELECT cutout switch and the STAB TRIM AUTOPILOT cutout switch, located on the control stand, are provided to allow the autopilot or [my emphasis] main electric trim inputs to be disconnected from the stabilizer trim motor." They are wired in parallel.
Takwxs, Appreciate the clarification.