B&M Auto Transmission Flex Plate for 360

B&M makes one for a 904 and one for the 727.
Two different part numbers. If I remember right,the 727 part is a tad to
big for a 904 trans.

Not true. The converter bolt pattern is exactly the same. How do I know?? Cause I just installed one for a 727 Trans on a 904 a couple days ago! It will even fit if you have a stock converter with 5/16 bolts because it is dual drilled for both 5/16 or 7/16 bolts.