I've got the 0411 and I'm planning on just porting and polishing my intake; hoping between a full rebuild with a bit of headwork, a Comp XR270, bigger injectors and plenty of tuning I'll be able to get to 400 horse. Still debating on going to aluminum heads but I really need a price comparison between a set of Brodix aluminum heads or the cost of machine work on my factory heads.
As far the intake upgrades, I think
@Scottm did some work using a factory one, and there's another guy with a Suburban who's running an aftermarket intake; I can't recall his name but maybe someone can chime in?