What have I got here? Magnum 5.9 Flex plate identification

Wow...ok... so in honesty, I have yet to try to fit the bell housing up to see if it fit. I just assumed that it had to be too big for the 904 since there are different parts for the 727 and the 904.

So if the flex plate does fit inside the bell housing, the trick will be finding a ring gear that will extends beyond the edge of the flex plate, right? Can these be swapped?

Thanks for the info, guys.