stumble/hesitation

so just hook up a vacuum gauge and adjust the idle mixture screws moving the vacuum up until it drops off and move em back to the spot with the highest vacuum?

Basically yes,, but the vacuum guage can tell so much more ...

Check out this link, and clic on the green tabs to see how many diff vac readings can guide you..

http://www.secondchancegarage.com/public/186.cfm

hope it helps..