How to tell what ive got

Look at the pan. if the pan is rectangular, you got a 904. If the pan is mostly rectangular with a "kickout" where the dipstick enters the pan it's a 727.

As for the bellhousing, This is all from memory so don't shoot me if I'm waay off. With the tranny in the normal position, measure the distance between the two top bolt holes. If it's a big block it's about 6-1/2", and the small block is around 7-1/2". Sounds bassackwards but thats the case.

Good luck!!! :salut: