If it’s any help the way I have done it on my quarter scale Bates Sea Fury is; -

Like you I have servo operated inner doors I have a micro switch for each door closing as the gear finishes it’s up stroke. I interrupt the neutral wire to each servo and pass it through the micro switch. The gear door servos are then “y’ed” to the retract channel.

The switches must “make” slightly before the end of travel so that the doors have enough time to fully open before the power is switched off.

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