i don't think you can use the old ecu. you'll have to get an ecu from the same generation as the motor (someone correct me if im wrong). if you don't use the standalone, i think you're making the job a LOT harder on yourself because of all the adaptations and workarounds you're going to have to do just to not have the ecu throw up when you try to start the car

 

na i was going to use the series 6 ecu..wire up stand alone bit furter dwn the track when i got more funds..