I have an 04 g35 coupe manual trans. I need an ecu, trying to buy one from junkyards and little bit confused. Dealer told me that i strictly need an ecu only from these productions dates 06/03 to 09/03 wondering if that is true? Also on my old computer it has following #MEC31-903 A1 3911. I can't seem to find the exact # I always see numbers that are close like #MEC31-901 A2 2134 or something is that normal?