Rebuilding my 73 charger

[Nacho-RT74]

actually even is true is not that hard than a 727, isn't soooo bad to hold a midly spiced SB, but also will depend on how is built and its internal components. Down here in Vzla ( and I bet also Brazil ) 904s are built for midly spiced 318s 4bbls and is hard to find someone getting broken a tranny. As far case is healthy and internals are good quality, will hold.

note, of course 904 was initially designed for /6s, thats why they were initially called Torque 6 trannies, and 727 were called Torque 8, for V8s applications... untill around 1963-1964 with the aluminium case born, 904s were used for SB V8s too.

For the swap... as far I know just get shortened the driveshaft  couple of inches maybe ( and propper TC ) and you will be done