since i wrote that post i haven't encountered a sleeve i couldn't pull out. i made a block of wood with a hole drilled in it to provide support for the coil itself. i have a nut driver that is the perfect fit to tap into the coil and push the sleeve out. i also use a socket that has a "stem" on it to chuck into a drill or changeable bit screwdriver. this works well for the really stubborn ones since holding the nut driver just so to get it started can be tricky at times.