Hey Siepher...why don't you write up a how-to on the auto to manual swap, now that you've done it? I think there are enough people around who would do it if they had some guidance. If you do, just skip the part about putting the pressure plate in backwards and fast-forward to installing the clutch properly the first time .
If you were to buy an auto GT (as rare as that is, though I've seen a handful in Pullman alone), would doing an auto to manual swap get you right up to the normal stock manual GT performance? I don't know why it wouldn't...it just seems a little weird *shrug*