Cut it off.
I either use my dremel or a 4-1/2 inch angle grinder with a thin cutting disc on it.[angle grinders much faster.]
I hold the grinder at an angle and work my way all around the shaft going slow as to not heat up the shaft and cook the rear seal.
The reason to hold it at a downward angle is so after its cut off it will be below the case and wont interfear with the mountng setup.
Another thing i do is add cold water as i go around the shaft.Make 2 passes,cold water,2 passes,cold water,ect...