Mower throttle Servo - how to build with manual over-ride

Hi, apols if answered elsewhere - im looking for pointers or suggestions.
How to connect servo to control a pull cable mower throttle.
I can build up the servo mount with no issues, but i’d like it to be “manually overridden” if need be, eg we can overpower the servo to shut or down (or up)
Im about to purchase a water proof servo for this task - any wisdom gladly received.
I can link in to the carb body, but assuming controlling the cable/lever is the way to go.
My throttle is similar to the one in the pic. Thanks
image