In the olden days when I had a Quadra 35 with a spring starter, I removed the sleeve. What I did was to lay the shaft/sleeve squarely on an anvil. I then smacked the sleeve with a hammer. It shattered like glass. It was put on with a transparent green sleeve adhesive made by Loctite. Once it sets up you can't get the sleeve off intact.

I imagine the next guy to reply will tell you how simple it is to remove intact.

Ken