None. It's just like throwing in a 904. The only special thing you need is the kick down which you should have if it's an automatic and not a manual valve body.
I checked your facebook and it looks like you're doing the same thing I did and since you already have a 904 it's just changing it out.
*source: I took out a \6 3 speed manual and put a 360/727 in mine.
in an early abody you will have to hammer over the firewall seam to get a 727 to fit in most cases. other then that the drive shaft is shorter and may have to use a cable kickdown.