I have a howling problem in the back side of my Cobra. I had a local shop set up some 4.10 gears for me. Rear seemed really tight when I got it back. I am afraid they had the turning torque set wrong. However, I was playing around, getting on it and off of it (wife had to pee) I think I may have screwed it up. I haven't taken it apart yet, but I think I have wasted my crush sleeve with my antics. It has gotten worse and worse, and now the car is parked waiting on me to climb under and fix it. My question is: Can I set up my turning force on the pinion and then pull it apart and machine a piece the same size as the new crush sleeve and simply replace it? Or is it a matter of shimming to get it right? I can set up the new gears myself now, don't know what I was thinking letting someone else turn a wrench on my car anyway. Thanks for your input! JON