Would a Chevy 12bolt rear be legal in your class? I remember several years back a few guys were using them in some Hemi Abodies. They are lighter than a Dana,absorb less power than a 9inch (attractive to a class racer)
and tons built. Should be able to build one to easily handle 400-500hp reasonably.Lots of used stuff also. Just a thought -if it's legal for your class. Bill