Ive been searching around for awhile now and I'm getting two screws on the carb confused. Theres one on the top of the carb that if unscrewed all the way let's the carb come off and another one on the tors system that is a flat head screw. Which of the two will acually adjust my idle speed? Sorry for the kind of stupid question but my manual kind of contradicts other info I'm hearing. Thanks!