I'm getting tired of not having a speedometer after "the swap". I'm missing the little gear that goes inside the case, with the square hole for the little adapter key in the end of it. I have a 203 back home, would the one from it fit in my 205? Would this oil leak stop if I put one in? Can I buy one somewhere? Is this what they change to calibrate the speedo, and if so is there a good speedo shop around that can help me out?