It is *possible* but ultimately depends on the strength of the portion of the monti which isn't attached directly to the plug. If it is relatively thin and a large percentage of the underside is encrusted to the plug then you may have a very difficult time getting it off in one piece. If it is "taller" and a smaller portion of the underside is encrusted then you could possibly take a razor blade or thin flat screwdriver and scrape/pop it off.
Really, though, I usually remove my frags from plugs and with a monti I would just inspect the plug closely, dip and cut the cylindrical mounting piece off the plug.