Well I still need to "tweak" my fuel system a tad.
I'm running a sump with -8 feed lines, a Bosch 390 inline pump, rails, 42# injectors with a 4:1 FMU, adjustable FPR and -6 return line.
I've got a second Bosch 390 I'm going to run in parallel and upgrade to 60# hi-impedance injectors and remove the FMU.
I'll need to retune but with just being able to fuel to slightly above 7,200rpm I should hit 600rwhp easily.
After that I think I'll look at a T-56 tranny to replace the stock T-45 (which is still holding up fine by the way).