On the carb question stock jetting should be fine. If you go to a dual exhaust you may need to richen them slightly.
One handy mod is to put an oxygen sensor in your exhaust and connect it to a volt meter. You can read off your mixture strength and adjust carbs accordingly.
There are several web sites that describe the process in detail if you do a Google search.
If you rebuild the carbs it would pay to fit the throttle plates as tight to the bore as possible. This will make it easier to get a good slow idle adjustment.
Carbs made for multi carb installations come with a thicker throttle plate that fits tighter for this reason.
