With the #2.0 you should be close on what you have, if you have a 17 pilot you might try that, the bigger the cut away the more are intake, so you need bigger pilot, that is why with 2.5 I use 25-30, the 190 and 200 we use on our 750 in my world that is to big for your 650, 175 at the most.(which will not effect the idle.
make sure all the passages are clean, where is you mixing screw set at , start at 1.5 turns out from the bottom(all the way in)
Do your slides open at the same time? Do the reach the top at the same time? Use your finger one at a time and open the carbs up until you feel the bottom of the slide is even with the carb cut out. match. , with your fingers on the slides of both carbs. see if they start to open at the same time. Match after you have that done,
As I don't know where you are starting with the slide , put a 3/16 or so drill bit in them (or one at a time) and adjust your idle screw to just touch them, be sure to pull them out before you start the bike. That's about all there is to setting up Mikuni.
let me know what you have for pilots, I have in the 17-22.5 range I will never use, with the 2.0 you should not need to go larger.