The above margarita recipe is a good place to start... but a good one will have as much as three times the ingredients. As many, even more than the Long Island and Zombie.
What else are you putting in your margarita? Three times the ingredients? ! I will say pure lime juice for a margarita is too sour. Needs some agave nectar and a splash of oj.
Screwdriver? You mean SONIC SCREWDRIVER!