that really is the best way. An invaluable tool for your bench is a pair of dividers, use them to get the right height and score the line on your metal to saw.
Also, use a heavy gauge metal; consider getting some 22g fine silver sheet and maybe some 18g fine silver for your bezels. Though it seems counter intuitive, the heavy bezel is far easier to work with than the thin, flimsy commercial bezel stock.