Iowa Code § 321.43: New identifying numbers.

The department may assign a distinguishing number to a vehicle when the vehicle identification number on the vehicle is destroyed or obliterated and issue to the owner a special plate bearing the distinguishing number which shall be affixed to the vehicle in a position to be determined by the director. The vehicle shall be registered and titled under the distinguishing number in lieu of the former vehicle identification number within thirty days of issuance of the distinguishing number.