You have to judge whether the piece looks glued on or cast integral to the model. If it's sticking out, with undercuts suggesting glued on, it's just a resin piece that can easily be removed. If it's moulded on in the porcelain type material that most of these have for the main body, then I have found no way to remove it except, in the case of this model, the gravestones that I managed to break off with a set of pliers because their form lent itself to that.