the 04+ cars are drive by wire, so you can't use that throttle body. if you swapped a gen 5 on for a top swap you would need an L67 to gen 5 throttle body adapter. all it is is a plate that bolts to the supercharger and then has places for the throttle body to bolt to. you would need L67 fuel rails, you L36 rails might work, but they might not have the correct spot to bolt down to. sometimes the heads get cracks inbetween the valves, so if there is a crack, that head is junk and you would need to find another. L32 heads do flow a little better than L67, but only by like 3%.
you wouldn't really need to port the gen 5 and lim, but you could gasket match the lim so there is less turbulence between the heads and the lim, and porting the heads will make a difference for sure. if you wanted to run a little more compression, you could shave the heads and use a thinner mls gasket, but you would likely have to run E85 or higher than pump gas fuel so it wouldn't have kr.
