D&D is located in Wixom MI. But they did get my clutch to me in less than 4 days. They do have a couple different clutches. One which is like stock and the other that is 50% stronger. Its good to 550-600HP. The 26 spline is as 93SVT said. Its just stronger. I figured while I was in ther just replace it so I will not have to do it later...