Chokes are one of the most challenging mechanism to set up on a non-factory arrangement.
There is a intial choke postion, choke pull-off (sometimes called qualification) to which it opens as soon as the engine fires up, fast idle, and sometimes some control of choke opening with termperature.
For now, don't worry about choke. Follow what crackedback wrote in post #9.
Fire it up and use the idle trottle stop screw to keep it running at 'fast idle'. Then turn the screw back to close the idle as needed. Make sure the choke flap stays open. Idling at 2000 rpm in neutral its not really going to need choke. Get your engine broken in without fouling plugs or washing down the cylinder walls.