Darren Smith with Pro Trans in Lancaster CA.

http://www.protransracing.com/

They are one of the premier Mopar and otherwise race trans builders and manufactures out there.

They manufacture on site many of the trick Mopar trans parts. Sometime repackaged and sold through other sources.

They can definitely build a 904 to handle that application. Just need to talk with them on how cost effective vs the benefits is that going to be vs a 727.