Yes the engines are identical except for the sparkplug, which is smaller (I bet?) - that change is not related to the auto choke though.

The choke on the carburettor is not special - the auto choke lies in the ignition only. The ignition just controls the choke servo, rather than your reciever. The ignition senses if the engine is about to quit (revs dropping), and subsequently it closes the choke a bit. If you are starting the engine, is senses no revs and closes the choke. When you flip the prop, and the the engine pops, the ignition immediately opens the choke. Should make for the easiest starting engine ever.