The newer than 2007 stock ECU causes trouble because they require all the inputs from sensors we don't use in the conversion to be present before the car will run. I hear they have some ways of making it work like having the stock gage cluster hooked up and hidden in the front trunk area as some SAS cars or a conversion box to hook inline that have varied reviews. This is the reason Special Edition only uses 2007 donor cars if they can help it. The 2007 is new enough the have the variable cam lift engine that puts out 173HP as opposed the 165hp that the earlier 2.5 liter engines offered. This may be a reason for after market ECU's.