SEM servo motor

I have some brand new SEM servo motors that I got on e-bay. P/N is
MT30H4-44. There is a tach in the back end where I want to put an
encoder. The problem is getting the tack out. It appears that the
outside permenant magnets are pressed or glued or something in place.
I made a puller but the screws pulled out. THEN I have to get the
armature off, which is going to be a real bugger. Has anyone had any
experiance getting these out. I was told they would just "pop"
out...........NOT! Any help would be greatly appricated.

Thanks, Tony