ok the c6 will work but it would not be good behind a 302, trust me. i had a truck with a 302 c6 and it took a lot of power to turn up to 60 more HP than a c4 actually. it is severely heavy, i had to carry one by myself. if you had a 429 or something then you could use it and be happy, it is a heavy duty tranny and i think one of the best that ford made.