Just what Brad said.
I recommend the hybrid almost every time, even with the automatic. In fact I don't like to deal with SHOShop anymore, but they have the best lower intake manifold mod on the market if you dont have any skills by yourself. You can do the swap, lightly port and polish your stock heads and throw on their modded lower intake manifold with 37mm secondary throttle blades.
Depending on mileage you may want to have the valves done then you could be more aggressive with your port and polish job on the heads, or even go the full 3L valve setup as I did.
Even with the atx you wont be disappointed. Oh yeah, if you don't have an SVT then the whole SVT upper/lower would work better, but = $$$
On an automatic it might be best to use your 2.5L heads as described above, the shoshop lower intake manifold, and then modify the 3L upper manifold to fit. It will flow better than the stock 2.5L upper manifold and give good torque gains where the automatic needs it most.
My $0.99 worth of advice.
warmonger
