Next up was the throttle servo. The firewall exit hole location was determined when the engine was mounted; I worked backward from there. The Futaba 3401 servo used is quick, for good throttle response, but that particular servo is shorter lengthwise through the case than normal. So a custom mount was called for.

Here's the finished installation.

Note the tri-stock to add rigidity, and the hole for the servo wire; quite important on flush-fit mounts like this.

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