Watched video showing how to replace blower wheel clamps. Demonstration was excellent but actual procedure was not as easy as depicted (to be expected). Encountered two difficulties. Reinstalling the belt was tough; the idler wheel torsion spring is very strong and hard to reach. Also, the new clamps do not fit very tightly on the motor shaft flat. I added a shim to the front clamp to improve the fit, but the wheel can still be rotated about 15 degrees on the shaft. I wrapped masking tape on the motor shaft to create a friction fit to the inside diameter of the blower wheel. Suspect that this is a design flaw and the reason the original clamps failed in the first place. Also the motor shaft is worn (grooved) just as discussed in the video.