I would just go with what pdxtex recommended and use a box cutter and indent lines into the shoe where your current cleats are. Can be precise since you can line the blade up against the cleat and cut exactly where it needs to go. I'll have to do this soon as well since my left cleat is looking a little worn, have wedges between my shoes and cleat so i may make two indentations to line up both so there exactly where they were.