1. "Alteration" means an unauthorized change in an instrument that purports to modify in any respect the obligation of a party to the instrument or an unauthorized addition of words or numbers or other change to an incomplete instrument relating to the obligation of any party to the instrument.
2. Except as provided in subsection 3, an alteration fraudulently made discharges any party whose obligation is affected by the alteration unless that party assents or is precluded from asserting the alteration. No other alteration discharges any party, and the instrument may be enforced according to its original terms.
3. A payor bank or drawee paying a fraudulently altered instrument or a person taking it for value, in good faith and without notice of the alteration, may enforce rights with respect to the instrument according to its original terms or in the case of an incomplete instrument altered by unauthorized completion, according to its terms as completed.