Question:
(1) Do you want to roll-back your own original odometer for some reason to a mileage that's less than the car's actual mileage? Or,...
(2) Are you acquiring a used, replacement odometer (because your original one broke) and you want to roll back the replacement to so that it indicates your car's actual mileage?

If it's the first, you might be liable for misrepresenting the car unless you have stickers that will endure through subsequent owners -- (although it's a remote possibility) let's consider that you sell your car (with the warning stickers) to someone who eventually removes the stickers. Then he sells the car to someone else by misrepresenting the mileage. Then that buyer finds out, and comes back to sue that guy and you, too.
On the other hand, on Titles in my state (not MA), I can fill it out (when I go to sell a car) indicating that the odometer does NOT represent the true mileage. Then, by making and keeping a copy of that Title, I can protect myself from any charge of misrepresenting the mileage (it would be presumed that any subsequent titles issued would bear the warning, "indicated mileage may not reflect true mileage".

On the other hand, if it's the second reason, then you're not misrepresenting anything, and you can go ahead as you please. The law doesn't care about aesthetics, but only odometer fraud, which you wouldn't be doing.