I ran a china carb and just used the S terminal on the back of the alternator. It worked fine that way with a little adjustment. The S terminal only has about 7v, but you can turn the black choke housing to suit your needs and make it run the way you like.
The great thing about the alternator connection, the choke only heats up when the engine is running. If you hook the choke to key on 12v, then it is pulling off as soon as you turn the key. If you happen to have a little problem with it starting, and the key is on but it is not running, the choke is pulling off the whole time. If it happens to be cold outside, and the choke pulls off too much, it may never start unless you pump the gas pedal several times before cranking.
You should always push the pedal to the floor at least once on a cold morning start by the way, even with a auto choke.
