I need to know what my 68 350 HO had originally for a shifter ball. It's a 4 spd Muncie with Hurst shifter. I currently have a silver, Hurst T-type handle but I don't think it is orginal. I believe originally it was a white or black ball with the 4 spd shift pattern. Which is it? white or black? What about thread size? My shifter seems to be 3/8" 16 threads per inch (coarse).