is there a huge difference in the rb25det s1 and s2neo ecu's? i have a s1 rb25det in my car but the ecu numbers come back as an s2 neo ecu. also the ecu does not have a diagnostic led or selector knob thing inside of it. is this normal for a series 2 neo ecu? the car seems to run pretty good. but this is my first rb25 so im just assuming its running normal. should i track down an s1 ecu or should i be fine with this one