I put one in my fastback, which has a C-6. We didn't have to remove the tranny, although my small hands came in VERY handy (no pun intended) in getting the cable onto the tranny. There is very, very little room with a C-6, 390, and headers. However, it was worth it, as it looks great and handles beautifully. I also went with the Lokar throttle cable shift set up, which eliminates the accelerator rod through the firewall.