I'm replacing a bathroom sink with a ceramic drop-in model. The new sink's cut-out template calls for a 17 3/4" dia. cut-out. Unfortunately, the current cut-out is just under 18 1/2" dia. I REALLY don't want to replace the counter and cut a new opening. I was thinking of putting some kind of shims or spacers around the opening, gluing and screwing 3/8" plywood strips around the inside of the cut-out. The counter is particle board covered with formica. I doubt whether I can get the plywood to bend around the opening, so I'll probably have to cut short strips and attach them end to end. The new sink is supposed to be secured to the counter with silicone caulk.
My questions: 1) is this a terrible idea? 2) if not, is there a product specifically made for this?
Any suggestions or ideas would be appreciated. Thanks in advance for your time.