Here are a couple pics that may help. In the 1st one, slide the rubber boot up on the choke cable to get it out of your way. If it's stuck, a squirt of WD-40 will free it up.
Now pull the cable up and down with the choke lever off. Watch the metal ferrule on the end of the cable...where the screwdriver is pointing....it should move up and down very easily at least 1/16 inch. ...absolutely as free as can be. ...If you continue to pull up on the cable you can feel when the choke plunger spring is resisting. As long as you have that free play, your choke plungers should be fully down, and not contributing to running rich.
In the 2nd pic...that is the idle mixture screw...don't hesitate to back it out more than 2 turns counterclockwise from being lightly seated. That lets more air in at idle speed....sometimes you have to play with them...try to keep both carbs close to the same. On warmer days...say 30 degrees, I often had to back those screws out at least 2 1/4 turns. Each sled is probably slightly different.