the 03-04 cobra t56 wont work becouse the shifter, like every other mustang tranny, is too far forward for our cars, same dimensions as the t-45. the tailhousing on the ls1 is about4-5 inches farther back,,, this is the reason the idea sprang up to use the ls1 t56 for our application but i beleive its still alittle short. the problem i have with that is the imput shaft of the ls1 t56 is a few millimeters off, might not be an issue but i like to have everything perfect. now, when gm came out with the gto, they ran into the same issue we have with our cars,, the location for the shifter is too far back to use any of the availible manual trannys. to solve the problem, they use what looks like the ls1 tailhousing, but the shifter used is sitting on a plastic base that moves the shifter back an additional 4 inches, making it more suited for our cars. this way is probably still pretty pricey,, but now we may be able to use the 03-04 cobra t56, mate it to a gto tailshaft and use the gto shifter and have perfect shifter location. i dont know about any of you, but im going to stop collecting parts for the t-45 swap and start saving for the t56 swap using this method.