I think you are looking at the free play adj. It stops the pedal so you don't get too much play in the cable. the top one is throttle stop. If you want to know for sure, just push the pedal all the way down and the screw that hits a stop is your throttle stop. You should be able to readjust it to stop just before the tab on the throttle body hits it's limit. I was able to get the throttle to open a little bit more by readjusting it.