I just got this kit myself. I bought the electric choke with it since my Carter didn't have one. Good catch on that hot air fitting, mine isn't plugged but does have a fitting. That is going to suck to replace now that it is installed
The directions are haphazard like you said, but there is enough info there to figure this kit out. I keep referencing back to them to make sure. I am only a few items away from being done with this project so I have my fingers crossed.
Also included in all the info sent is the Nutter Bypass stuff. It could be better written and the info is available on-line if you get stuck. Not included are any directions on setting up the carb once installed. I'll wing it I suppose. Can't wait to fire this thing up.