You mean to say that you're going from stock to Stage 5 in one giant leap? Not a smart move. Especially if you're posting questions like this one. That's big time. You realize you're not looking at plug and play, bolt on and go with that sort of system, right? With great power comes great responsibility. The slightest mistake at those levels and poof! It's all gone and you have a crater where your 420A once was.

Good luck to you. HRC kits are quality and you should be able to install it just fine. Well, I think that if you're running a Stage 5 turbosystem, you should be required to be able to at least install it yourself.