You have to pull the motor barring the aforementioned frame mod. There are a couple of ways to do this. Either remove as much from the engine as you can, starter and all that jazz, and heave the motor out. It is heavy, around 170 pounds or so so any weight you lose will help.
You might fashion a bracket to bolt to the motor and use a hoist to help move it out of the frame. You could also lay the bike over and then remove a bunch off the bike and lift the frame off the motor.