First thing I would do is take it to a garage and have an emission tester put on and see whats going on.That will tell you if it's the idle,mid range or high speed jets that need to be worked on or maybe a combo of things.You got to have a starting point when it comes to carbs.You could spend a ton of time and money buying jets and parts and never get it right.The only other way is to get a setup "factory" carb and manifold and install it.
Pete
