During construction I felt that the electrical gear circuitry had several potential failure modes, so I installed a heavy wire from the battery + terminal to a 40 amp self resetting circuit breaker, to a high current push
button switch mounted on the baggage compartment bulkhead, to the down wire of the gear motor.
I can pull the 50 amp breaker and push the button to bypass most electrical failure modes. The push button switch is recessed in the bulkhead and covered by an aluminum plate and tape to avoid accidental activation by baggage impact.
To test the pressure switch, connect a long piece of tubing to the pitot tube, bend it in half to create a metering orifice and blow gently into it while watching the airspeed indicator, with gear up selected (on jacks naturally). When the switch closes the gear should come up.