I was just informed by my tuner/mechanic that I have a distributor with a .426" shaft on it and that my .491 polymer gear I ordered does not fit. I thought our cars all had a shaft diameter of .491"? I had to order a gear from Crane Cams and its made out of Aluminum/Bronze and its .426" It will last a little longer then a bronze gear but not as long as a polymer gear which is the one I wanted to run since I am running a billet gear. What gives here? The dist. I have to use is out of a 1990 Formula.