Welcome to LMF....
Are you thinking you may not be around very long, and don't want your mower running once your gone?
Actually I think you are wanting an operator present switch... something like a seat switch. Not sure why you want to ass one, most folks are trying to figure out how to defeat them...
But if you really want to do it get a seat switch that has a set of contacts that are normally Closed. .. Two wire hook up,
1. to the kill wire either at key switch OR on engine....
2. Hook it up to ground any convinent place on the frame or engine...
When you are setting on the seat it will be open, when you ?fall? off it will close killing the engine.... If you bounce up and down you will get a lot of backfire that will eventually destroy your muffler and cause you to want to remove it... like many others want to do... :smile:KennyV