B&M Auto Transmission Flex Plate for 360

63dartman said
Just because it fits may not mean it's right. I would call B&M and ask them why there are two different part numbers for the 904 and 727 and go from there. I could be wrong though.

You are wrong! Last time I checked a Trans has nothing to do with the balance of an engine. If it bolts up it will work, plain and simple.