Ditto that, Michael.
And @Stan Galat I'm totally in agreement about the CB/Tomlinson books. John Connolly really knows his way around Webers and I learned quite a lot reading his comments on thesamba.com. Mark Harney was a treasure to learn from as well. There are a lot of good older carb setup threads that both men commented on.
Honestly, four things are needed: cleanliness of carbs, absolutely equal air and fuel(carb setup), precise and maximum spark, and a wideband O2 sensor.
But reading what the sensor is telling you is the harder part.