Good Luck with your quest for the 10s ! I am the same way the guy that builds my 904s used to run a Stocker for Chrysler back in the early 70s and really knows his stuff and has been doing my transmissions for over 40 years. He does all kind of tricks inside and they must work as the 904 behind my 410 inch small block has been in the car 7 years now. He also built me a complete ready to go spare 904 in case I ever need it for the simple reason : he is getting up there in age being in his mid 80s. If you can swing it .. it might be good idea to have your other 727 gone thru also .. always good to have a ready to go spare especially in the middle of a race season.