You don't need a bezel removal tool, I used one at first then realised you don't need one at all !. In fact with hind sight that was poor advice. Easiest way is a "Stanley knife" blade, go under the bezel at the 11 O,clock mark and lever steadily up, don't try and remove it in one go, although it may come off.
If it won't come off but will lift slightly, move to the 1 O'clock marker and do the same, it should lever off nicely. Don't be over forceful, just steady, ease it off.
you'll see why these points are critical to removing it safely when you have got it off. There are also two more lever points at 5 and 7 markers.