Need help IDing 727's

Well, all slant 6 transmission are 904..

A way to ID a small block 727 and a big block 727 is just look the bell housing. Big difference.. or like Fishy said.

Also, to tell a 904 and 727 diff is look at the pan, 727 is much bigger, has a bulge on the front right. Also a rib on the casing.

Hope this helps.