C6 should be fine Dago. Thats what's going into my 48, the rear will be a 71 f150 9 inch, and the power plant is a 429 with 350-400 hp. I've talked to quite a few folks that say the c6's are bullet proof! If you go over 500hp, you start getting out of my range of knowledge, but I'm sure one of our Ford guys will know!