I have a holley on my truck I am trying to sell. I need to fix the carb asap. I have a 3310 750 vac. secondary. It is running very rich. I got on a site to see how to adjust but they will not tell you , you have to buy a book. But the site did say if you adjust the air mixture screws all the way in and the motor does not die you have a problem, well mine keeps running but runs better. What do I do to fix this. I have someone coming to look at the truck tomorrow and I need this fixed, also carb was rebuilt last week. Thank you Ricky..