If you order a car they can make it any color you wish. Check out the site from the link a few replies above and see the choices they have. They are always changing also.
As for a 427 SO with a top loader, the sky is the limit since each dealer is individual in their building/sourcing of drivetrains. Unfortunately (if I am not mistaken) the only 427 option that will fit the Backdraft is a 427W. That is a 427 Windsor (a stroked 351) the official small block/big block
. That is what ran at Run-N-Gun. It had 600hp and the M option suspension and rear end. It was sort of a demo for Backdraft to put to rest anyones concerns about how much power a BMW rear end can handle.