I was working on me Stugs. return rollers the other day, figuring out how to cut the mounts off without making mess of it. Use a razer saw and pry the back off. The saw will make a nice cut.

Jaws

Jaws:

Lee Valley makes cut-off saws with teeth only bent/sharpened to one side to do just this thing. Fine tooth as well... just F.Y.I.