Exploding Torqueflites

Yes true. We used to do it in Stock and Super Stock. It takes some special parts to do it. You can not just put the 904 internals into a 727 case. Pro Trans in Riverside, California has all the information on this. They also have a straight cut low gear package for the 727. I use it to get my Cordoba 360 of the line.
The reason to use the 904 internals in the 727 was to get that last possible tenth or hundredth when racing in NHRA. This is called "CHEATING". Won some races. Not worth the expense, unless you are racing Stock or Super Stock. However, I'm sure that NHRA is wise to the practice, as they were closing in on it around the early 70's. That is my 2cents. Good luck on your in devours.
joemac1j