I just got my rotor puller today in the mail. I threaded it in there until it stopped, held the crank in place, and tried to ratchet it in there farther. I'm coming across the same leverage issue, would it be best to use an impact from this point to get the job done?
The "puller" doesn't do all the work by itself. Run it in as tight as you can, Then tap it hard with a steel hammer, That should allow it to turn in some more. Then tap it again. Its the shock from the tapping that breaks the seal of the taper, not how hard you can initially tighten the tool. 3 repetitions ought to do it, may take more
BTW: you can't hit the tool too hard so when i say tap it, I mean TAP it.
PS: You could hit it with the impact I suppose. That might even do it right away. I've just never done it that way.