I'm looking to totally boost up my power in my 68 cougar XR7 as most of you know. I've asked about what engine I should put in and I think I'm pretty set on a 351W stroked to a 396. So now I'm looking at transmissions. Right now the car has a c4 automatic. I'm thinking with over 400 hp, I'm going to need to beef up that transmission. Really, I'd like to put in a manual transmission, a nice 5 speed would be great, but I don't know how hard and costly it's going to be to drop in a manual transmission. Has anyone ever done it? Also I'm looking to have the ability to still be able to fully restore the car when I'm done being a kid, so I'm keeping that in mind to. So I'm looking through transmissions and I see this transmission that has a manual/automatic valve body. When it's in drive it's an automatic, but when you shift into a low gear it becomes manual and you need to shift after that. Does anyone know how these things work? Should I just convert to a manual transmission? Or can I just get away with a shift kit? and that's another thing I don't really understand, is how a shift kit works and what are their advantages? Thanks for your help, because I sure need it!