After several attempts by myself, my wife, and one of my neighbors, I had another neighbor stop by (the one who actually owns this machine) and he was able to get the sheave to come off after about 30 minutes of trying. Apparently I wasn't being gentle enough with it and was rocking it too far in one direction when trying to remove it. He just barely moved it and it started rocking down the shaft!! Glad that it finally came off, now to the rest of the tear down.