Thanks so much for the info! I was able to locate the switch, and it looks fine. The throttle itself is sticky, however. When you put it to STOP, the cable goes a bit loose, and the throttle does not close all the way. However, you can easily push it the last 1/4 inch though by hand and it kills the motor right away like it's supposed to.
It doesn't look like there are any adjustments. I tried cleaning it out as best I could, and also put a bit of WD-40 on the spot where it pivots, but it still is rough closing on that last little bit. I might just leave it as is, since at least now I know all I need to do is reach down and push the throttle closed all the way to shut it off.
Thanks again for the help.