On your deal I would look at using a Mopar brand 2.77 low gear set and a steel drum I'm sure Cope can do that for you, I live west of the big muddy so I use Dave Smith at Pro Trans for all of my 727 tranny builds I can do them myself but he has all the little parts needed (thrust washers, snap rings and so on) to set the end play up correctly inside the tranny and a ton more knowledge on torqueflytes than I do so he gets my tranny work