I will agree with Grimracer, and Dick Loeb. After using the OS lower for some time now, if I am doing a 3.5 installation, its going to be an OS. Now, I use a custom made stand off, and buy the fullers or hyperformance collet, BUT I now use Kris Flynn's flex cable. He makes me a cable that is OS length, one end has an OS square, and the other has a K&B size square so it fits properly in the collet. Hope that helps, Mike L.