3rd gen manifold the cold air intake is the same, the intercooler tube will be the same, as well as exhaust. With the 2nd gen u need to modify all of those. Not a big deal, just not a simple bolt and go. I had the 2nd gen setup on the 03 and it was nice, i also bought everything all setup though.
I'm not a fan of internal gates and pluming an exgate a mild upgraded daily driver isn't needed. I've had several reccomend non gated 66/74/14 for the 6.7.
E.D. builds the"better bullet" that gets good reviews.
if its a stock 3rd gen mani then u have to go t-3, other wise i'd for sure go t-4 for flow.