We have a specific part number from ididit to use # 11206800XX for 67-68 and 15207900xx for the 69. These have 1" 48 spline ends that match up to the steering shaft kit . Then we move it up (vertically) about 1.5" at the firewall plate, just enought for the ujoint to clear the frame. We end up adding some material to the bottom of the factory firewall clamp/ mount plate and trimming off the top. if your doing a different set up with some other arrangement then you may have more options.