I looked at the wire diagram. It is too much trouble for the conversion. The main thing is that the connector for the controls are different. The non-auto-temp version does not have bunch of wires in the middle. But the auto-temp uses another sunlight sensor, in-cabin air temp sensor (little hole by the driverside, by your right knee) and outside air temp sensor. I was tempted to just 'wire-up those sensor to the controller, but it turns out I need the pig-tail for the auto controller.
Other than those three sensor, I think mechanically, both systems are same. By the looks of things in the FSM, both have same blower motor and other 'valves' to divert the air.
So, I haven't installed it yet. I am just waiting for the harness to show up on ebay...