I am building a mild 340 for a 73 RR, street only with 323 or 355 gears. Should I try to find a 727A or just use the 904 I have laying here? Which trans would have likely come in this car? 904 or 727. It is an orig 340 auto car. Data tag is too rusted to read. I have a 904 and am looking for a 727A without luck so far.